[VoiceOps] AT&T LRN Issue?

Anyone from AT&T monitoring here? We have a customer that some AT&T customers cannot dial. I'm guessing it's related to a stale LRN. We ran into this recently with Windstream, and it was a bear to get addressed... but they finally did and admitted the error on their end. Or... anyone have a good channel to contact AT&T for such issues? Thank you, Mark