Sorry for the lack of clarity, I have figured this out and will detail it in case someone makes the same mistake I made. I have been working with EE to long to make this type of mistake, but figured detailing may help others.
What this looked like on my end: The field type appear to install correctly, but when attempting to edit a page using this field type, I could not add or edit any of my list items.
What I did wrong: I accidentally uploaded the field type code to both
themes/third_party. Obviously the module's theme code needs to go in the themes folder, but in a rush to update I accidentally made this incorrect upload.
How I found the problem: I went to an edit page containing the List field type and did an inspect element. Then noticed 404 errors saying that the field type's css and js couldn't be found. Since these were supposed to be located in the
themes/third_party folder, checking this folder I found the incorrect folder had been uploaded.
Solution: (Which is very obvious at this point) Upload the modules theme folder to the server's