I recently bought a new 955 and I have loved it so far, I did have a problem with it receiving SMS messages and followed all the advice online and still couldn't figure out what was wrong. I contacted support and they lead me though the same steps were fine and just got to the end of the list and immedtly sent me an RMA and disconnected.
This didn't make any sense at the time. I tried ti communicate that everything on the device (i.e. I received all messages from the device, calendar email etc. and anything with blue tooth was fine was working but SMS. The hardware was fine it was a software issue.
Simple sending me a new device which is the same as me resetting the device wouldn't fix anything and would take weeks to happen.
.Not happy with that answer I spent a little bit more time and found out that the app on my phone needed to be reinstalled. iI run android and did this going into Settings - Apps - Storage and hitting the one to clear the app from my device which reinstalled it.
Poof everything worked fine, saving us both the cost of having to do an RMA.
In order to improve on this experience, I would recommend three things:
1) a hardware check tool that will tell you in the hardware is working on a device
2) Adding two more fixes to your support checklist including resetting/reinstalling the Connect App and resetting the device to a factory default.
Please let me know if there are nay questions
Jusdtin.