IPhone 6 "No Service"

my iphone 6 has had no service for the last two days. I have contacted both Apple and Fido for assistance:

Fido suggestions:

- reset network settings

- toggle airplane mode

- fido signal reset

- remove and re-install sim

- try different sim (no luck)

- try current sim on different phone (worked on wifes phone)

after all attempts failed fido asked me to contact Apple.

Apple suggestions:

- toggle airplane mode

- turn phone off/on

- reset network settings

- reset phone

- update to IOS 8,3

- back-up and restore to factory settings

after all attempts lead to failure apple ran a "quick" diagnostic and showed that the iphone was in "perfect working order". They then asked me to recontact my service provider.

could this be a hardware issue? would the diagnostic pick that up? please help