The 27/04/2022 I sent 2302 UST from Binance to Kucoin but I forget the memo.
For Kucoin the only solution is to transfer back the UST to the sending address without memo as you can see on their standart answer.
Firstly, I asked to Binance if I can recover my coins like that an they answered me it's no possible.

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Shelly (KuCoin)
Apr 27, 2022, 16:18 GMT+8
Dear Valued KuCoin User,
Thank you for reaching out to KuCoin customer support.
Your deposit can't be credited to your KuCoin account since you did not fill out the correct Memo/Tag/Message (Which you can find from the deposit page). However, KuCoin may assist with the recovery indiscretion and to the extent feasible due to the pertinent process that may contain significant resource consumption as well as time and risk cost. Thus we will require a processing fee of 50 USDT.
Kindly note that USDT is developed on a different chain (USDT-ERC20 / USDT-TRC20) so please kindly check the type of your USDT first and then send 50 USDT to the relative address firstly:
USDT-TRC20: TQm9De49aXmvzqBSaTd1iVHtEN2egSGw2C
USDT-ERC20: 0x156f4f224ccf2f67855cc067d3182d65c5830302
Kindly Notice:
1. If you agree, please give us the relative transaction screenshot and the txid of the fee after you have paid it. Please note the processing fee is 50 USDT. If the paid fee is less than that, certain difficulties will be caused in the process.
2. Our only solution to this issue is returning the token to the sending address without Memo/Tag/Message.
3. Before you take our solution, please ensure the receiving party could credit the token to your account without Memo/Tag/Message. They may charge you a commission fee.
Please read the above statement of instructions carefully and reply to us in the email if you confirm to apply for the recovery service. If you have any questions or concerns regarding this process, please don't hesitate to let us know.
Kind regards,
KuCoin Customer Care and Support Team"
Finally, Kucoin have no solution to transfer me back my coins. Kucoin keeps my coin on their wallet. Sort of Scam?
TX : 7C6E3D273541EF4701347FD959B18940F52F96A002E758DCB1B7CCEFC1B31815
Request : 1778328