Type is blocked in Prepare a Form, even after signatures removed

I created a PDF document with form fills and a signature line, and I was able to type into the boxes. When I needed to use the form, I was then unable to type in any of the forms, and instead received a highlighted section (pictured below). I did some research and apparently once a signature is added (even just the form for a signature), it won't let the forms be filled out. 

So I rebuilt it from a Word document, imported it, and made sure that it wouldn't automatically add any form fills. I manually put in all the form fills, minus the siganture lines, and it still gave me the error.

Please advise. I've made plently of documents before with forms and signatures and have never encountered this issue.