Pamac fails to authenticate

Hi all,
After Manjaro 24.0 update I am having issues with pamac. Issuing an update as follows, fails to authenticate and never exits:

$ pamac update
Preparing...
Synchronizing package databases...
Refreshing AUR...                                                                                                                                                                                                                                                                                                                                                                                                                           
Cloning google-chrome build files...                                                                                                                                                                                                                                                                                                                                                                                                        
Generating google-chrome information...
Checking google-chrome dependencies...
Warning: plymouth: local (24.004.60-6) is newer than extra (22.02.122-18)
Resolving dependencies...
Checking inter-conflicts...

To upgrade (8):
  nvidia-utils        550.90.07-3      (550.90.07-2)       extra  
  firefox             127.0-1          (126.0.1-1)         extra  
  firefox-i18n-de     127.0-1          (126.0.1-1)         extra  
  firefox-i18n-en-us  127.0-1          (126.0.1-1)         extra  
  linux66-nvidia      550.90.07-3      (550.90.07-2)       extra  
  linux68-nvidia      550.90.07-5      (550.90.07-4)       extra  
  mhwd-nvidia         550.90.07-3      (550.90.07-2)       extra  
  opencl-nvidia       550.90.07-3      (550.90.07-2)       extra  
To build (1):
  google-chrome       126.0.6478.55-1  (125.0.6422.141-1)  AUR

Total installed size: 1,3 MB

Edit build files : [e] 
Apply transaction ? [e/y/N] y

==== AUTHENTICATING FOR org.manjaro.pamac.commit ====
Authentication is required to install, update, or remove packages
Authenticating as: phil
Password: 
Cancelled
==== AUTHENTICATION FAILED ====

Issuing first a pacman update and then pamac does work:

$ sudo pacman -Syyu
[sudo] password for phil: 
:: Synchronizing package databases...
 core                                                                                                                                                                                                                                140,6 KiB   593 KiB/s 00:00 [--------------------------------------------------------------------------------------------------------------------------------------------------------------------] 100%
 extra                                                                                                                                                                                                                                 8,3 MiB  5,79 MiB/s 00:01 [--------------------------------------------------------------------------------------------------------------------------------------------------------------------] 100%
 multilib                                                                                                                                                                                                                            144,7 KiB   548 KiB/s 00:00 [--------------------------------------------------------------------------------------------------------------------------------------------------------------------] 100%
:: Starting full system upgrade...
warning: plymouth: local (24.004.60-6) is newer than extra (22.02.122-18)
resolving dependencies...
looking for conflicting packages...

Packages (8) firefox-127.0-1  firefox-i18n-de-127.0-1  firefox-i18n-en-us-127.0-1  linux66-nvidia-550.90.07-3  linux68-nvidia-550.90.07-5  mhwd-nvidia-550.90.07-3  nvidia-utils-550.90.07-3  opencl-nvidia-550.90.07-3

Total Installed Size:  960,53 MiB
Net Upgrade Size:        1,27 MiB

:: Proceed with installation? [Y/n] y

(( skipped for brevity ))

==> Initcpio image generation successful
( 8/12) Refreshing PackageKit...
( 9/12) Reloading system bus configuration...
(10/12) Copy Firefox Distribution Settings
(11/12) Updating icon theme caches...
(12/12) Updating the desktop file MIME type cache...
$ pamac update
Preparing...
Synchronizing package databases...
Cloning google-chrome build files...                                                                                                                                                                                                                                                                                                                                                                                                        
Generating google-chrome information...
Checking google-chrome dependencies...
Warning: plymouth: local (24.004.60-6) is newer than extra (22.02.122-18)
Resolving dependencies...
Checking inter-conflicts...

To build (1):
  google-chrome  126.0.6478.55-1  (125.0.6422.141-1)  AUR


Edit build files : [e] 
Apply transaction ? [e/y/N] y

==== AUTHENTICATING FOR org.manjaro.pamac.commit ====
Authentication is required to install, update, or remove packages
Authenticating as: phil
Password: 
==== AUTHENTICATION COMPLETE ====

Building google-chrome...
==> Making package: google-chrome 126.0.6478.55-1 (Mi 12 Jun 2024 14:30:15 CEST)

(( skipped for brevity ))

Upgrading google-chrome (125.0.6422.141-1 -> 126.0.6478.55-1)...                                                                                                                                                                                                                                                                                                                                                                       [1/1]
Running post-transaction hooks...
Arming ConditionNeedsUpdate...                                                                                                                                                                                                                                                                                                                                                                                                         [1/4]
Refreshing PackageKit...                                                                                                                                                                                                                                                                                                                                                                                                               [2/4]
Updating icon theme caches...                                                                                                                                                                                                                                                                                                                                                                                                          [3/4]
Updating the desktop file MIME type cache...                                                                                                                                                                                                                                                                                                                                                                                           [4/4]
Transaction successfully finished.

polkit is running:

$ ps -elf | grep polkit
4 S polkitd      701       1  0  80   0 - 97023 -      11:48 ?        00:00:00 /usr/lib/polkit-1/polkitd --no-debug
0 S phil        1217     986  0  80   0 - 165936 -     14:25 ?        00:00:00 /usr/lib/polkit-kde-authentication-agent-1

pacnews are processed:

$ pacdiff

$

Any suggestion on what may be the issue?

Thanks

journalctl around the time of pamac failure:

Jun 12 14:25:57 desk systemd[1]: proc-sys-fs-binfmt_misc.automount: Got automount request for /proc/sys/fs/binfmt_misc, triggered by 1615 (AUTHENTICATE)
Jun 12 14:25:57 desk systemd[1]: Mounting Arbitrary Executable File Formats File System...
Jun 12 14:25:57 desk systemd[1]: Mounted Arbitrary Executable File Formats File System.
Jun 12 14:25:58 desk systemd[1]: pamac-daemon.service: Deactivated successfully.
Jun 12 14:25:58 desk systemd[1]: pamac-daemon.service: Consumed 1.827s CPU time.
Jun 12 14:25:58 desk baloo_file_extractor[1880]: kf.idletime: Could not find any system poller plugin
Jun 12 14:25:58 desk baloo_file_extractor[1880]: qt.core.qobject.connect: QObject::connect(KAbstractIdleTimePoller, KIdleTime): invalid nullptr parameter
Jun 12 14:25:58 desk baloo_file_extractor[1880]: qt.core.qobject.connect: QObject::connect(KAbstractIdleTimePoller, KIdleTime): invalid nullptr parameter
Jun 12 14:25:59 desk pamac-tray-plas[1430]: updates_checker.vala:100: 9 updates found
Jun 12 14:26:00 desk systemd[1]: Starting Pamac Daemon...
Jun 12 14:26:00 desk systemd[1]: Stopping User Manager for UID 964...
Jun 12 14:26:00 desk systemd[818]: Activating special unit Exit the Session...
Jun 12 14:26:00 desk systemd[818]: Stopped target Main User Target.
Jun 12 14:26:00 desk systemd[818]: Stopped target Basic System.
Jun 12 14:26:00 desk systemd[818]: Stopped target Paths.
Jun 12 14:26:00 desk systemd[818]: Stopped target Sockets.
Jun 12 14:26:00 desk systemd[818]: Stopped target Timers.
Jun 12 14:26:00 desk systemd[818]: Closed GnuPG network certificate management daemon.
Jun 12 14:26:00 desk systemd[818]: Closed GnuPG cryptographic agent and passphrase cache (access for web browsers).
Jun 12 14:26:00 desk systemd[818]: Closed GnuPG cryptographic agent and passphrase cache (restricted).
Jun 12 14:26:00 desk systemd[818]: Closed GnuPG cryptographic agent (ssh-agent emulation).
Jun 12 14:26:00 desk systemd[818]: Closed GnuPG cryptographic agent and passphrase cache.
Jun 12 14:26:00 desk systemd[818]: Closed GnuPG public key management service.
Jun 12 14:26:00 desk systemd[818]: Closed p11-kit server.
Jun 12 14:26:00 desk systemd[818]: Closed PipeWire PulseAudio.
Jun 12 14:26:00 desk systemd[818]: Closed PipeWire Multimedia System Sockets.
Jun 12 14:26:00 desk dbus-broker[834]: Dispatched 185 messages @ 1(±2)μs / message.
Jun 12 14:26:00 desk systemd[818]: Stopping D-Bus User Message Bus...
Jun 12 14:26:00 desk systemd[818]: Stopped D-Bus User Message Bus.
Jun 12 14:26:00 desk systemd[818]: Removed slice User Core Session Slice.
Jun 12 14:26:00 desk systemd[818]: Closed D-Bus User Message Bus Socket.
Jun 12 14:26:00 desk systemd[818]: Removed slice User Application Slice.
Jun 12 14:26:00 desk systemd[818]: Reached target Shutdown.
Jun 12 14:26:00 desk systemd[818]: Finished Exit the Session.
Jun 12 14:26:00 desk systemd[818]: Reached target Exit the Session.
Jun 12 14:26:00 desk systemd[1]: Started Pamac Daemon.
Jun 12 14:26:00 desk polkitd[701]: Registered Authentication Agent for unix-process:1891:946020 (system bus name :1.86 [pkttyagent], object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8)
Jun 12 14:26:00 desk (sd-pam)[820]: pam_unix(systemd-user:session): session closed for user sddm
Jun 12 14:26:00 desk systemd[1]: user@964.service: Deactivated successfully.
Jun 12 14:26:00 desk systemd[1]: Stopped User Manager for UID 964.
Jun 12 14:26:00 desk systemd[1]: Stopping User Runtime Directory /run/user/964...
Jun 12 14:26:00 desk systemd[1]: run-user-964.mount: Deactivated successfully.
Jun 12 14:26:00 desk systemd[1]: user-runtime-dir@964.service: Deactivated successfully.
Jun 12 14:26:00 desk systemd[1]: Stopped User Runtime Directory /run/user/964.
Jun 12 14:26:00 desk systemd[1]: Removed slice User Slice of UID 964.
Jun 12 14:26:00 desk systemd[1]: user-964.slice: Consumed 6.621s CPU time.
Jun 12 14:26:02 desk systemd[1]: dbus-:1.3-org.kde.powerdevil.discretegpuhelper@0.service: Deactivated successfully.
Jun 12 14:26:02 desk systemd[1]: dbus-:1.3-org.kde.powerdevil.backlighthelper@0.service: Deactivated successfully.
Jun 12 14:26:04 desk systemd[1]: dbus-:1.3-org.kde.powerdevil.chargethresholdhelper@0.service: Deactivated successfully.
Jun 12 14:26:06 desk pamac-tray-plas[1430]: updates_checker.vala:70: check updates
Jun 12 14:26:09 desk systemd[1]: pamac-daemon.service: Deactivated successfully.
Jun 12 14:26:09 desk systemd[1]: pamac-daemon.service: Consumed 1.705s CPU time.
Jun 12 14:26:10 desk pamac-tray-plas[1430]: updates_checker.vala:100: 9 updates found
Jun 12 14:26:21 desk systemd[1]: systemd-localed.service: Deactivated successfully.
Jun 12 14:26:22 desk systemd[1]: systemd-hostnamed.service: Deactivated successfully.