How do I fix the Error "At Least one required field was empty. Please fill in the required field ...

I am using PDF. As I said I am a novice at this. Perhaps for others like me you might provide some really complete directions on what information is needed and what is extraneous to any question. The form was sent out using the instructions provided when completing the form. I “distributed” it to myself to ensure that it worked properly and got the following message. I then saved a copy of the document opened it and attached it to an email and tried again…..same result. I have tried a number of different ways but every time I hit submit to return the document, I get this message. There are no required elements in the construction of the document that I put in.

I read threads that this happens to others but the only one that I could understand said something about a button field (I had no button fields) and besides that the steps to fix the problem had me looking for icons or buttons that I don’t even see in my version of Acrobate DC Pro.

I am an assiduous manual and direction reader. I find that most of them were written for versions long past. If you can help me I would truly appreciate it; I am inclosing the info on the document in question, maybe you can find something in it that will tell you what I did wrong
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