Can't enter WiFi password in AppleTV

I had to change the password in my WiFi router. When I went to update the password in AppleTV, I selected the WiFi router, then it said that the password was incorrect. Yep. Clicked on OK. And just got the spinner "wait" icon... forever. Shut everything off and turned it back on. No good. Same result over and over. How can I get to the screen to enter the new password, or forget this network and start over? Just stuck.