You transferred USDT from one blockchain (BEP20) to another blockchain ERC20. ERC20 is an Ethereum blockchain. It is not possible to transfer directly, only by exchanging through a bridge or some exchanger. You can forget about your USDT.
The reason why Op has not seen his transaction in his wallet his because kucoin suspended BEP20 for usdt assuming it was other tokens Op would have been his transaction because both ERC20 and BEP20 are the same in kucoin(I checked for busd and some other tokens).
So technically it was not because he transferred from one blockchian to another, and with replies, I have seen and read so far there's still hope that he'll receive his Usdt back so it's still too early for him to give up on his coin.