Hello irenej,
I'm JS a contributor here. Where are you using your phone? At home, in a building, office, elevator, etc? If you are in a building, office or elevator you may experience no signal as there is concrete all around you and radio waves cannot travel through concrete.
For trouble shooting try turning the phone off, counting 5 seconds, turning the phone back on as that may reset the signal bars, go outside to use your phone or the communication connection between your phone and TELUS might be temporarily out of service. If these ideas don't work then I would call TELUS Technical Support at *611 and they may be able to fix the problem.
