Hello,
You description of what is occurring has me at a loss for recommendations. I believe you should reach out to Apple Support as this is a very uncommon scenario.
If your Apple ID existed you wouldn't be able to create a new Apple ID with its email address and if it was deleted you wouldn't have been able to re use the original Apple ID email address,
How to delete your Apple ID account - Apple Support
"Can I use the primary email address for my deleted Apple ID account to create a new Apple ID or with another existing Apple ID account?
No, once your Apple ID is deleted, you can't use the email address that you used with it to create a new Apple ID. In addition, you can't use that email address with another existing Apple ID except as a rescue email. Also, if your primary Apple ID email address is with a Custom Email Domain, it can never be reused to create an Apple ID after your Apple ID is deleted, even if the domain ownership changes."
My only suggestion is to check your email to make sure you are correct with which email you had as your Apple ID.
If you forgot your Apple ID email address or phone number - Apple Support
https://getsupport.apple.com/topics
I hope this helps.