I currently bought a house and it seemed that ATT is already providing service to the address via a third party(told by a representative). They told us to email the address verification to get our proof of ownership for the home. We called again ATT to get an update and it seems this new representative told us they do not cancel service, that we needed to contact the previous owner or the company providing the service to get it cancelled(stupid honestly).
So ATT my advice, please make this process a little easier for your customers. An address validation should not take days when all the closing papers are sent. Heck, there is even the County Tax, where you can look up addresses and their current owners. Do not be stupid we are on 2021 and you are a technology company which should not this.
Train your representative better, so next time they know what you answer and do not ping pong people with nonsense. Also, please whenever a customer ask to be ESCALATED to a SUPERVISOR, make sure your support staff complains and do not provide answer like "the supervisor will say the same thing I am telling you." Or else do not have supervisors at all.