I submitted a ticket to both ATT and NTT today. The technician at ATT said that it has been escalated and gave me a contact to provide details to the "backend team", and the response received from NTT was:
"I have associated this to our master ticket. I cannot disclose the full details but know that this incident is escalated to the highest level within NTT. I would advise continuing to create tickets with your upstream provider, ATT, to bring attention and awareness to the impact this is having on you and other ATT customers."