How to recover Facebook account where hacker changed email?

Somehow, my Facebook account has been hacked. The password was a strong password stored in 1Password so I have no idea how it could have happened in the first place, but I guess that's the second step to figure out. My guess is that there was some 3rd-party integration that was hacked and that lead to my account being hacked, but as far as I know, I haven't used any 3rd-party integrations that could have that type of access to my account. My 1password account has likely not been compromised either, as only the Facebook account has been affected.

The problem is that this Facebook account was mainly used to run ads for a professional Instagram account, which now has also been suspended.

The hacker apparently has deleted the account (the account is not visible on Facebook anymore) and the email associated with the account was changed from a @gmail.com to a @hotmail account.

All the "My account has been compromised" or "I was hacked" support guides/tools that Facebook offers, are assuming the email is still the same for the account, so I can't seem to get any help from those.

Also, there doesn't seem to be a way for me to actually contact Facebook support in any direct way, to get a human to help me.

So in short: How can a person who is literally giving Facebook money for a service get any sort of help with these sort of issues?