Hey there, there is no workaround to unlink an account you can't access, you'd have to work with Steam to try to recover. Bungie does not forcibly unlink accounts. Or - if you don't mind losing all of your code-redeemed emblems and Bungie digital rewards (these are all tied to your Bungie Account), create a dummy Epic account and link it, then log in through epic and unlink your XBox account (you can't unlink XBox while you're using XBox to log in, that's why there's a new account involved). With your XBox account now unlinked, you can link to your new Steam. However just to reiterate, you've now split your XBox account off from your original Bungie Account to make a new one, and will lose access to your old code-redeemed emblems, Bungie digital rewards, possibly a few other things. Anything earned directly in-game will be safe. Additionally even if you did decide you wanted to play using Epic, you'd be unable to set up cross-save without being able to authenticate that old Steam account.