trackpad not responding

I watched a video on a website and the MacBook Air went to sleep overnight. . . Installed Catalina OS about a week ago. When I woke it this morning, no trackpad at ALL. Dead.

Reset PRAM, no joy.

Restarted in SAFE mode. .. some joy: the cursor responded from trackpad UNTIL I put in my password at Login Screen. Then, dead to touch.

USB and magic mouse work fine. SO, using the mouse to get around as default. I really would like my trackpad back though!

Suggestions for further sleuthing?

It worked fine for last 2 weeks after installing Catalina. . . until NOW.