Welcome to the community, @gahq! Maybe this post discussed previously should help you understand your issue:
Copy ox7sa54
Under the choices sheet Press CRTL+F
Then paste ox7sa54
You should now see the duplicate names. Fix it and you should be able to solve your issue. As a further check, you could also validate your xlsform through this online validator to see if there are any other syntax issues present within your xlsform.