[Q] Unregistered Sim with Note 3 unlocked (originally on rogers) topic

Hi there,
I was coming home from the cottage went thru a dead zone with no service.
when I looked back down at my phone it said unregistered sim card...
with the phone being unlocked.. instantly thought blacklisted....
My sim works in other phones just wont register on this phone.. however I tried to put another sim from my mothers bell and it brought up bell on the phone.
I have contacted telus my provider and they just keep saying its something with your phone because my card works elsewhere in other phones,

I just purchased this phone I could really use some help with this.

Thank you