Manjaro can't boot after update

I have two manjaro in seprate hard drives in my system
I have access to tty and other one manjaro
but I dont have idea, what I have to do
just in last time I use this command for driver :thinking:

mhwd -i pci video-linux

sudo mhwd -r pci $(mhwd -li | grep ‘video-’ | awk ‘{print $1}’
sudo mhwd -a pci free 0300

sudo mhwd -r pci $(mhwd -li | grep 'video-' | awk '{print $1}' 

sudo mhwd -a pci free 0300 
> Skipping already installed config 'video-linux for device: 0000:01:00.0 (0300:10de:0fe1) Display controller nVidia Corporation GK107M (GeForce GT 730M) 
> Skipping already installed config 'video-linux for device: 0000:00:02.0 (0300:8086:0166) Display controller Intel Corporation 3rd Gen Core processor Graphics Controller

what should I do next?

Looks like corrupt Kernel/Grub.
sudo grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=manjaro --recheck --verbose
sudo grub-mkconfig -o /boot/grub/grub.cfg
Another idea:
one of the manjaros should be invoked by: /etc/grub.d/40_custom
using chainloading (!!!)
as updating / changing of the kernel on one installation
will not be recognized by the second installation;
( the boot-entry of one installation is not updated and will not work?!)
Only example:,typically used for Windows

menuentry "Windows C " {
insmod part_msdos
insmod ntfs
set root=’(hd0,msdos1)’
drivemap -s (hd0) ${root}
chainloader +1

sudo grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=manjaro --recheck --verbose 
Installing for x86_64-efi platform. 
Installation finished. No error reported.

sudo grub-mkconfig -o /boot/grub/grub.cfg
Generating grub configuration file ...
Found theme: /usr/share/grub/thenes/nan jaro/theme.txt 
Found linux inage: /boot/umlinuz-5.9-x86_64 
Found initrd inage: /boot/intel-ucode. ing /boot/initranfs-5.9-x86_64. ing 
Found initrd fallback image: /boot/ 
Found Manjaro Linux (20.2.1) on /deusdb1 Adding boot menu entry for UEFI Firmware Settings ... Found mentest86+ image: /boot/memtest86+/memtest.bin done took 15s

#noob :frowning_face:

Two times Manjaro is like one time linux and one time windoofs.
You need two independent bootloaders - one must be the “master”.
The “master” boots the msters OS AND/OR the “slave” (second) OS.
One bootloader is not enough: if one OS changes the kernel-version,
the other cannot know this - as the second OS is not involved in upgrading (!!!)
→ and will fail to boot…