work for a company in the US that has an after hours support line for IT related issues and we have notifications setup to ring to our mobile phones with SMS notifications. Unfortunately, we have several users that have T-Mobile as their carrier and are forced to go the route of using their firstname.lastname@example.org since that carrier is not listed. They are not receiving notifications for missed phone calls or left voice messages. Previously they were able to get notifications up until today.
I have AT&T as my carrier and can receive the notifications normally without problems, so I am wondering if this is a carrier related issue or if the problem is with RingCentral. We have a rotation set each week and each user has to manually go into the notification settings and remove the current user before adding themselves in for that nights on-call shift.
Currently I do not have another T-Mobile user available to check this with but I have removed and re-added the user that is having the problems number several times as well as enabling notifications for most of the options. Emails are being sent out to the specified one, but SMS notifications do not go through.
Any help is appreciated.