Latitude 5285 2-in-1 touch screen not work after BIOS 1.23 updated

It is trouble day for me, my Latitude 5285 2-in-1 touch screen does work any more after update BIOS 1.23,

and the BIOS 1.23 locked downgrade, so I cannot recover older BIOS.

I trid to reinstall Windows 10 and apply all lasted driver and Windows update, touch screen still not workable. help me please, Dell or any workable solutiontion, many thanks.

by the way, in device management, all components are actived by driver included touch screen, so it is not hareward problem.