Reload nvidia GPU driver
Reload nvidia GPU driver to fix "NVML: Driver/library version mismatch" error without rebooting. Source
The following command will switch the system into text (CLI) mode, reload the graphical driver, and then switch back to GUI mode.
sudo apt purge $DRIVER_TO_DELETE
sudo apt reinstall $DRIVER_OF_CHOICE
sudo systemctl isolate multi-user.target
lsmod | grep nvidia # - to identify the modules needing to be reloaded.
sudo moprobe --remove $ALL_MODULES_IDENTIFIED_ABOVE
sudo insmod $ALL_MODULES_IDENTIFIED_ABOVE
sudo systemctl isolate graphical.target