What I noticed is that every time I click on the Delete button, a hashtag appears at the end of the web address. In fact, when I hover over each add and delete button, I see the same web address, which is:
I have tested it on my test site and it’s working fine for me using latest version of Shapely theme.
This can be due to plugin conflict on your site so please try temporary deactivating all plugins and see whether everything works fine and then enable the plugins one by one to see which plugin is conflicting if any.