Alright - here’s where we are at and why we have been looking into this for so long.
The account yuan.gm was created on Nov 14th - but you tried to create it on Nov 20th. If that wasn’t you on the 14th, it means that someone else created an account with that name before you and controls that account. This we believe explains why you can’t access that account or perform any transactions.
We have done an extensive review of our systems and identified three bugs that, if all occurred at the same time, could have resulted in a situation like this. This is a situation where both the checks in Anchor and on our servers could have been bypassed, and allowed you to seemingly create the account, even though it already existed on chain. This however requires very specific network conditions and having all that happen at once is ridiculously improbable, like winning the lottery and being struck by lightning at the same time improbable, but since we believe your story and you have a backup sheet for that account - it’s the only explanation we can come up with.
If you aren’t the person who created yuan.gm on the 14th your only recourse is to try to contact them and ask to transfer the tokens back to one of your other accounts. The account has been active on chain as of the 14th, so someone is in possession of the key the account was created with.
Contacting another account holder can be difficult, since there’s no personally identifiable information involved in account creation or on the blockchain. You basically have to send a very small amount of tokens to the account with a memo attached, explaining the situation, but even then there’s no way for that user to know you truly are the person who deposited those tokens.