NOK 5G21 Gateway Battery Backup

Same issue here!  Just received my device 4 days ago.  The power went out the following day for about 15 minutes and I lost my signal.  Perfect timing!  My friend has the other model (TM-RTL-102) and she does not lose her connection.  When I called to order originally, I verified the battery back up thinking it would be the same as my friend's device.  Guess I should have phrased the question differently. I called T-Mobile this AM and the rep told me the reason I lose the signal is because of "a lockout in my area".  I'm baffled by that answer since the manual says the wifi and ethernet will be lost without power.  The rep thought my device was defective and wanted to send a new one out.  I turned that down.  What good would that do if it's the same model?