Sadly XLM is not supported by Metamask directly so is probably you tried to get a wrapped coin in BSC. If you like extension wallets you can use xBull Wallet (I created the wallet).
Now, about your XLMs you will need to check is you have a coin in your wallet that says something related to XLM and check the site of the issuer of the coin to know learn how to send that coin to the real Stellar Network