Can't edit a link in a PDF

I have a pdf with a table of contents linking to the appropriate section. That works just fine. I also added links at the bottom of each section to take the reader back to the TOC. Some of those links are going to the wrong location and I'm unable to select the link in order to edit it. I can edit the TOC links, but not the return links.

I go into Edit - Link - Add/Edit Link, but I am unable to select the links.

Thoughts?

Thank you!