Single user form stuck in submit loop

Hi,
I have a working form with no particular issues except one submitted form by a user. This user filled out form is submitted everyday for the last 5 days. It’s stuck in a submit loop. I couldn’t find anything in the forums so far.

Anyone have a suggestion on how to stop this loop?

I have tried to change the form to see if that would break the loop, no success.
Other form users and submissions have no problems.