Hi @AvaPatterson
Thanks for your question. I've given this a quick test and the pop ups seem to be working as expected for me so hopefully we can work out why this is not working for you.
Just to check, are you editing the pop up within the pop up tab in the web map viewer?
I assume your configuration looks similar to the above screenshot with all fields removed and just the title present? Could you confirm that once you save this web map and navigate to experience builder, the pop ups appear differently than within your web map?
Thanks!
Issy