Hey, In order to deactivate cross save and then unlink the account you will need to be able to authenticate all of the platform accounts, without valid credentials this will be impossible. Bungie cannot/will not remove any accounts on someone's behalf for security reasons, they also have no influence over the platform accounts so cannot assist with the password reset. You will need to work with [url=https://help.steampowered.com/en/]Steam Support[/url] in order to recover your your account, once the details have been recovered and you can authenticate all accounts, you will be able to deactivate cross save. [i]Also Note: Once cross save is deactivated you will have to wait the mandatory 90 day period before activating cross save again. [/i]

Nope! Bungie cannot unlink anything. If you do not have access to the account why would Bungie? You are responsible for all accounts on all platforms. Nothing can be done if account cannot be retrieved.