Form field issues

I am working to tag and improve a PDF document that was created in 2016. This doc has multiple form fields, and over the course of tagging and cleaning up the file, a few of the text fields seem to be corrupted - and I have no idea how to proceed.

I tried to auto-tag this doc, but cleaning up the generated tags was more effort than just tagging manually from scratch.

In the attached screen capture, a text field that was fine at one point now appears as a generic, non-editable "Field" that I cannot delete or change. Looking in the Annotations under the Content panel and in the Fields list while Using "Prepare a Form", there is no reference to this Field. It seems like it has been corrupted, but I don't know how to get rid of it. Any ideas?