Hi There @PJ1
Thanks for writing in! Did you publish your Convertplus Modal before testing? Also make sure that you have added
# for your button link.
Further, you need to disable your 3rd party plugins except Cornerstone and ConvertPlus plugin and see if you're encountering a plugin conflict. If the issue is resolved, then you can activate your plugins one by one to see which plugin causing the issue.
If you're using a child theme, disable it temporarily to see whether your child theme customizations causing the issue.
In case if you cannot isolate the issue, provide us with your WordPress login credentials in a secure note with your example page URL that you have setup the modal popup, to investigate it further.