Deassociate user with after sign with apple

Hello there, I've implemented signing with apple and successfully retrieve access_token but if the user either don't share his email or use an email already used on our website we want to kind of dissociate the user with our app / cancel sign with apple, so I'm curious if this is possible in php (with curl for example) and if it is, how?

Thanks in advance

Deassociate user with after sign with apple
 
 
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