Gamertag change , cant do custom challenges

So I changed my Gamertag
now when i make a custom challenge it shows my old gamertag “created by myoldgt”
and it wont let me turn them in.

Is there a way to fix this?

I have tried the following:
Recover my account
play a game of Matchmaking

nothing is fixing it…

You have to wait sadly, it takes a while to update.

As for your new name, that is just immature.

Nice to meet you. All of my gamertags are like this. I just cant seem to outgrow it.

thanks for the reply, i am also talking to xbox support chat, and they say there is no fix. so im asking them to change my gamertag back… i hope they do it, i want to play reach…