Cannot Convert Adult Account to Child Account - Server Error

I tried canceling and re-submitting the request from my son's Apple ID, but despite the dialog saying that the family account manager would receive an authentication request I did not receive one. It only sent me the request once (and accepting that one produced the server error message).

Assuming I could try again, why would another WiFi network make a difference? That's interesting, so curious about that.

I did call Apple Support and was escalated to a "senior advisor" who said he'd put in a request for a manual age change, supposed to hear back tomorrow. I'll see what happens then.

I doubt that connection is an issue, but if it comes up again I'll try. I'll update this post with the outcome of Apple's manual attempt to correct the birthdate.

PS. Why was the birthdate off? Special needs adult who needed a few more years of parental supervision beyond age 18. For better or worse that time is past. We want to get him an Apple Card and need birthday fixed to avoid problems.

Update: I was escalated a couple of times through support and then told a request would be sent for Apple to fix the date today. I haven't gotten anything back yet, when I contacted chat support with my case number they said to wait until next week. So I'll wait.

(I wonder if this bug is related to the introduction of family sharing for Apple cards. Age gets more important.)

Now 3 days since Apple said the Apple ID birthday would be updated and no change so far. Attempts to do this per Apple's directions still fail with a server error message. I've scheduled a chat follow-up next week using the same ticket number.

No response from Apple and no fix so far. I'll try Chat again Monday pm. I did write this up in a blog post:

https://tech.kateva.org/2021/07/unable-to-update-date-of-birth.html

PS. I'd copied the title of this thread from a 2020 post, but it's sadly misleading (my fault). I'm trying to convert him from child to adult, the prior post was about converting from adult to child. (He's over 13, I know we can't do anything with under 13.)

I called again and was again transferred from chat to phone to senior advisor who then was able (seemed indirect) to read an engineering response saying it was not possible to change a child age to an adult age. (They didn't explain why this shows a server error!)

This is contrary to Apple's documentation HT204164 which says only ages under 13 require an Apple support call to change.

Either Apple has changed policy without updating documentation or the engineer is confused. I have asked to reescalate to engineering with reference to the support doc. If that fails I suppose I could try changing his date of birth to be closer to adult (if that's possible) then when he ages to adult change it again.

I'm pretty sure this is a bug ("server error" is not a normal error message) but I also wonder if enabling Apple card on an account locks birth dates and that Apple engineering doesn't know that.

Update 7/24/2021: Support didn't call back on the date they'd promised. There's still a server error. As noted above Support seemed unaware of the contents of HT204164.

I'm going to have to give up on fixing this for now. I'll try again in a few months, maybe by then Apple will know how to fix the problem. I suspect it's something in their database design that's very hard to fix.

Glad for the suggestion but that would break an immense amount of stuff.

I tried canceling the request to parent then resubmitting the change, but after the initial email no further emails have been generated.