usb_modeswitch failing to start

Manjaro on pinebook 1080.

I am trying to use a usb "modem" to connect to internet but I get this error:

[leandro@pinobianco ~]$ sudo systemctl status usb_modeswitch@2-1.2.service 
[sudo] password di leandro: 
● usb_modeswitch@2-1.2.service - USB_ModeSwitch_2-1.2
   Loaded: loaded (/usr/lib/systemd/system/usb_modeswitch@.service; static; vendor preset: disabled)
   Active: failed (Result: exit-code) since Thu 2019-06-20 00:30:40 CEST; 1min 56s ago
  Process: 675 ExecStart=/usr/sbin/usb_modeswitch_dispatcher --switch-mode 2-1.2 (code=exited, status=1/FAILURE)
 Main PID: 675 (code=exited, status=1/FAILURE)

giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]: "if [regexp {ok:busdev} $report] {
giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]:         if [CheckSuccess $devdir] {
giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]:                 Log "Mode switching was successful, found $usb(idVendo>
giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]:     (procedure "Main" line 282)
giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]:     invoked from within
giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]: "Main $argv $argc"
giu 20 00:30:40 pinobianco usb_modeswitch_dispatcher[675]:     (file "/usr/sbin/usb_modeswitch_dispatcher" line 1005)
giu 20 00:30:40 pinobianco systemd[1]: usb_modeswitch@2-1.2.service: Main process exited, code=exited, status=1/FAILURE
giu 20 00:30:40 pinobianco systemd[1]: usb_modeswitch@2-1.2.service: Failed with result 'exit-code'.
giu 20 00:30:40 pinobianco systemd[1]: Failed to start USB_ModeSwitch_2-1.2.

Little more information.

The error show in the previous post happens when I insert the usb adapter from vodafone with usb id:

Bus 002 Device 005: ID 0af0:7501 Option Globetrotter HSUPA Modem (icon 411 aka "Vodafone K3760")

Before the usb_modeswitch does not show anything.