Verify With Receipt
The best way to tell if this charge is fraudulent is to find the receipt. You may have an electronic copy of the receipt, which you can finding by searching in your email accounts for AT&T.
Or, if you want to automatically find and reconcile receipts so you never worry about fraud, you can use SimplyWise to automatically match all bank and credit card transactions to email and paper receipts. The app instantly reconciles your expenses and flags anything that doesn’t match.