Contact
I deleted a contact and may have blocked in error
is there a way to retrieve that contact back ?
iPhone XS Max, iOS 13
To see the phone numbers, contacts, and email addresses that you've blocked from Phone, FaceTime, Messages, or Mail:
Go to Settings > Phone. Under Call Silencing and Blocked Contacts, tap Blocked Contacts to see the list.
You may find more information from the Apple Support link provided below: