Download another Garuda version, not KDE lite of all things.
Under Garuda-Welcome start chroot, grub-install, update-grub. Then see what garuda-update tells you.
If you have a M$ dualboot, you have to repeat update-grub after booting.
I did it this way on two notebooks and no problems since, unfortunately it doesn’t seem to work this way on all devices. Maybe use this then.