I’d be happy to help with the spam messages you have been receiving! I’d recommend sending us the details of the message by forwarding the entire message (along with the full header if it's an email) to email@example.com.
Another option to block shortcode messages would be to add a Purchase Blocker to your line. This would also prevent charging app or content purchases to your bill, however. You can add this through your myAT&T account from the Manage my Plan and Services option in the I WANT TO menu!
I hope this helps!
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