Non recognition of my e-mail by Apple.
I have an e-mail address but my iPhone will not let me use it, I am told that it is used already. Yes by me for the last twenty years!
How can I get my iPad and iPhone to recognise it?
iPhone 13
In what manner are you attempting to "use" this email address with (presumably) your iPad? You obviously can't re-register an existing email address that identifies an existing AppleID / Apple Account.
Perhaps you are attempting to set-up a new device? If so, you don't need to create a new AppleID; you should simply sign-in (when prompted) using your existing AppleID (as identified by your email address).
If you are attempting something else, you'll need to provide more information. What is perhaps obvious to you when looking at the problem, isn't obvious to someone else who only has the explicit information that you have provided.
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