I have been trying to troubleshoot this since last October. I have had several different cell phones since I have lived in my location over the last 6 years. I live in a condo and our phone number is plugged into a call box so that when someone arrives at our building, they find us on the call box, press Call and it rings our phone. We then press 9 to unlatch the front door. It suddenly stopped working last October. Around that same time I switched phones. Both were Samsung, but different models. Our call box was replaced around that time as well. I have tried to work with Samsung and the entry system people to no avail. When I say stopped working, I mean when I press 9, the door would not unlatch. It would sometimes work if I tried calling myself outside the building from the call box. In the past week it doesn't even ring my phone anymore, it goes straight to voice mail. So I don't know someone is outside unless they call my cell phone directly. Could this be a coverage issue? I'm trying this forum since Samsung has been trying but is unable to resolve the issue. The entry system company doesn't do much but they have tried taking the number out, putting it back in, or taking it out and putting in another number. Other numbers work. Most of my neighbors either don't use the front entrance or are in FL most of the year. One neighbor uses a landline, my neighbor next door uses AT&T I think. When I moved here over 6 years ago, I had to drop Verizon because we could not get coverage here. AT&T didn't work either. Neighbors recommended TMobile. I don't have any other phone issues.
Sorry this is long, but I am hoping someone will be able to help. If there is a TMobile Mod, if we can't resolve through this forum, perhaps it's a coverage issue that TMobile needs to look at.