Buyer try to scam me (pls help!)

Few weeks ago i sell a $10 Xbox Live code which i bought from amazon, some guy bought it (username: Camden Hilton), after 20 minutes he dispute the transaction, i asked why and he said the code is invalid. I asked Microsoft about the code and they told me that the code was redeemed that day at 15:43:01 UTC. The funny thing is that he bought the code at 15:35 UTC. I am a legit seller have +150 positive reviews and i always check the codes and i never try to do something wrong, and he has a bad reputation

Xbox Support Screenshoot:

Invite code: 9VGVQL
My profile:
His profile: /profile/us-east-1:e1fa093f-1e82-41aa-a035-d157bdd93e5a
Trasaction ID: 55fca7a6-f562-4f12-ad39-0a1dc11991c3
I already sent a ticket to support : #193329

Someone can give some advice, or if a moderator see this please help me, I don’t want to be scammed

Btw sorry for my bad english.

I just checked your account and solved your case for you.