New Mac Mini M4 Pro with Studio Display - constantly flipping to login screen

I recently installed a Mac Mini M4Pro with a Studio Display. Also got a new keyboard and mouse. I am clearly doing something to this very sensitive keyboard. I will be mid sentence on a document and suddenly the login screen appears, forcing me to either hit the touch button or type in my password to get back to what I was just doing. At first I thought it had something to do with the space bar, but have now realized that it isn't limited to that. It can happen just when I start typing. I checked for keyboard shortcuts in settings, but haven't found any that cause the login screen to appear. Does anyone have a similar experience or any thoughts on what I can do to troubleshoot? I am running Sequoia 15.2 but will update tonight to 15.3. Thanks!