Regions Bank security phone number.
Another number used is:
205-420-4225They call the phone number on file if they detect unusual charges on your Regions debit card account.
If you do not have a Regions bank account, it may have been an error on their end as to the phone number linked to the account in question.
Of course, it could also be a scam call with the criminals spoofing the real Region's number.
As always, just call the number on your account statement or on the back of your card if you receive any type of call about your account, that way even if it call was a scam, you won't be taken.