I received BUSD into my ethereum wallet and on checking my wallet I found out that it was on Binance smart chain. I know ethereum wallet supports ERC20 tokens and I really don't understand how BSC token was sent into the wallet.

Please, I'll like to know how to move the BUSD out of the wallet and if I'll pay the gas fee with ethereum or BNB. I have the seed of the ethereum wallet. The ethereum wallet was opened from the defunct Imtoken wallet.

Your advice and suggestions would be greatly appreciated.