Without having the actual real information it's hard to tell where the error lies and we can only guess. The witness is not allowed to be the same as the model or contributor, did you get that right? Also, there a different formats for dates. I looked at an accepted model release date of mine and I used the date format "day.month.year", so with dots instead of lines inbetween and day and month switched. It seems like such a minor and not important thing, but who knows what reviewers are thinking these days. On my property releases I actually always write the month out, to make it is clear what is the day and what the month, like: "14. Jun. 2022".
Also, the signature needs to be the actual signature, not just the name typed in (again, can't tell whether you did that without seeing the real thing).
That's all I can think of.