You can also create a “copy of” theme and in its code, try to remove any code that you think could be causing the issue and see if it works. Typical code would be something like: {% include ‘popup’ %} or similar.
If it works you can do it in the live theme too, but be very careful as you don’t want to break the live theme code and shop.
Thanks for your answer. I tried deleting all the loox code but the popup still appeared. So I checked the other apps that I had installed and realized that Klaviyo also has a function to add popups. That’s where it was! I was able to delete it from the Klaviyo app.