Hey there @Abbie Smith , thanks for checking out Zapier! =)
It looks like this issue you are having is happening on the Teamup website and not Zapier.com. Teamup uses a very modern type of authentication called “OAuth” : Zapier redirects you to the Teamup website and your username and password validation occurs completely on their servers. Once it is successful, they redirect your data back to Zapier with the tokens we need to interact with their API on your behalf and everything is (usually) great!
It looks like in the past when folks have reported this issue, that when they navigated to this page and added Zapier manually, they were able to select a Profile in the screenshot you shared. I would recommend going there and then retrying to see if this helps first.
If not, since this error is not happening on Zapier I would encourage you to reach out to the Teamup support team. They can for sure tell you what is going on!
Let us know how it goes!