This is commonly known as Chargeback. Here's a brief description:
There is the ability to gift someone sponsorship on MCSG. You can decide who the rank goes to. When someone attempts a Chargeback, they gift a sponsorship to a random person. This is where all the credit card information comes in. When the rank is already given, and the transaction is about to go through, the person who randomly gives the donor stops the transaction, and the money is refunded to the person, so they lose no money.
However, the diamond rank is kept, so the person essentially has a free donor rank. Now this wouldn't be so bad, as we could just remove the rank, and go on with our day. There is a complication though. When the transaction is canceled, MCSG is charged $20 for the charged back transaction. This means that we lose money, and the issue is not resolved by only removing the rank. Because of this, MCSG has to ban the player of which the rank was assigned.
Tips for avoiding being charged back:
Don't accept donor from strangers - If someone randomly comes up to you, and offers you donor, do not accept it. Especially if you don't trust them.
Realize what to do if you randomly get donor - Sometimes you could log on and have donor without knowing that you bought it. This could mean that someone has gifted you donor, and not notified you? Contact an administrator or another member of staff immediately to get the rank removed. The charge back will not be of any cost to you, and everything will be fine.
If you've been banned for Chargeback:
Sadly, the only way to get un-banned from MCSG if you were banned for Chargeback is to pay the $20 fine that was issued to MCSG at the time of the transaction. I believe this can be found in the MCGamer shop. NOTE: This does not apply to any bans other than chargeback. If you were banned for abuse, hacking, or anything other than chargeback, paying this fine will do nothing. You will not be unbanned!
Hope this helped :3
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