Realistically you have 3 choices 1 - leave it deactivated 2 - regain access to it 3 - use a throwaway to unlink your accounts you do have, but you'll lose redeem code emblems, bungie friend list, potentially name change tokens/have your name reverted, partner rewards - basically anything tied to the Bungie account itself. To do it: - Create a throwaway Twitch account and link it to your current Bungie profile - Sign out of Bungie.net and sign back in as the throwaway Twitch - Unlink all of the platform accounts you do have access to - Sign out of Bungie.net - If you've done it all, then you are done with that account - Use the Join Up option and pick a platform, finish setting up the account then link your other platform accounts.