I moved your question to its own thread so that it will not appear that it has been answered.[Split from this thread]
Please review How to post a question on this MSOffice forum.

Which kind of form field?

• Content Control?
  • Rich Text?
  • Plain Text?
• Legacy Text Form Field?

Which mode of Editing Restriction have you applied?


Please attach a copy (perhaps redacted) of your problem form. (document, not screenshot)
How to attach a screenshot or file in this forum.

References:

• Create a Form Using Word Content Controls by Greg Maxey
• Making Forms with Microsoft Word