Starting sometime midday 5/7/19 I stopped receiving all MMS messages. I assumed that was the extent of the problem but it turns out I am not receiving standard SMS messages from all but, as far as I can tell 4 numbers. I have an S7 and have tried the default Samsung messages app and the Google messages app that I normally use. Below is part of my message to customer support. I am still waiting for a response from them, in the meantime does anyone else have any suggestions?
Some more info on the issue I am having is that I am not receiving messages. I thought it was just group (MMS) messages at first but have discovered today that i also am not receiving messages directly from a single sender (SMS i assume). I know that I missed messages from a Galaxy 8 Note (?) that I believe is on AT&T, a newer Iphone on AT&T, another newer Iphone on an unknown network, Galaxy S6 on AT&T. The only two numbers that i have found to be able to receive messages from are a Galaxy S7 Edge on Cricket, a Nokia 7.1 on AT&T, an Iphone 5C on AT&T and an Iphone 7s on AT&T (IMessages is active on this device).
With the online chat support we checked the APN settings and refreshed the sim card/network but nothing has worked so far.
I don't know what happend but I am now receiving 3 days worth of messages so it seems to have fixed itself.