Guest Key Reset

If you are referring to the guest key, check this out:
support.xbox.com/.../forgot-guest-key

A forgotten guest key can be reset by any adult as long as that person knows the password that they use to sign in to their Microsoft account on the console. The adult must be signed in on the console to reset the guest key.

Hey Tan thanks for taking the time to bring this issue to us!

Unfortunately no, the way around this is to add the account and when it asks for the

passkey (on purpose) get it wrong 3 times. If done correctly it is going to ask for the Microsoft Account Password type that in and it will ask to set up a new Passkey. Give it a shot and let us know if we can further assist in this or any other issue!

check this link:

https://support.xbox.com/my-account/security/forgot-guest-key

Hello NikkiKruik,

Thank you for keeping us updated. A forgotten guest key can be reset by any adult, as long as that person knows their Microsoft account password and is signed in on the console.

1. Follow the steps to remove a guest key.
2. When you’re prompted to enter the guest key, enter an incorrect key three times, and then enter your Microsoft account password to remove the guest key.
3. If you want to create a new guest key, select Create a guest key and follow the steps

Those would be the only steps for forgotten passkey that we have on the support article linked above. At this point, please follow the steps in the second link above for a factory reset. I'll go ahead and link it here for you as well: Factory
reset

A forgotten guest key can be reset by any adult, as long as that person knows their Microsoft account password and is signed in on the console.

1. Follow the steps to remove a guest key.
   
2. When you’re prompted to enter the guest key, enter an incorrect key three times, and then enter your Microsoft account password to remove the guest key.
   
3. If you want to create a new guest key, select Create a guest key and follow the steps.
   

In your case, since you deleted your Microsoft account, I would recommend creating a new one as that would be the only option!