Hello @LunaLuna , welcome to MetaMask community.
The transaction shows that it was sent successfully but , it was sent to a contract address as it is on the image attached . I think it’s a wrong address (contract) .
0xB9bb89419fae1d690b6129E9819963eF155803C2
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This is my DMM bitcoin address.
I was thinking of sending ETH to this address.
However, in DMM’s support center said
“If the network setting at the time of transmission is BSN, we will not be able to follow up or reflect accounts.”
Will I have no choice but to give up trying to get my funds back?
The only thing remaining is to contact the respective platform to which you sent the ETH on BNB Mainnet. Your coins are there and only they can help you in this case. The transaction was successful when sent from MetaMask, which means it should have arrived successfully on the other side.