I have had this issue several times, especially when after doing some updates, or sleep.
I generally solved this by rebooting into the BIOS (alt-F4 to get power off options in Windows) and making a minor change and back again then saving the BIOS setup (and shut down – not reboot) then restart from cold and then everything back to normal.
This is resolved even easier on Linux. No need to enter BIOS. Just run these two commands in a terminal window and the touchpad should be restored to working: sudo modprobe -rv i2c_hid sudo modprobe -v i2c_hid