Microphone stops and error message every 10 minutes on Zoom fitness class meeting

I teach an online fitness class. Have successfully mixed my external microphone and shared computer sound for 3 years. Had to buy a new PC this month, Dell Inspiron laptop running Windows 11. Got an interface box Focusrite 2i2 to connect my microphone to my PC, as my old set up with a mixer and line-in through the head phone jack would not work with the new computer. 

All runs great until about 10 minutes of the class then the microphone turns off and I get a message on Zoom that says, "microphone not detected, please reconnect."  I open audio settings, click off of the Microphone setting, then click back to it and the mike works again. Then it all happens again in another ten minutes. And on and on.

I've searched the interwebs high and low for some answer to this. So far nothing has worked. Thanks for any help!