no service after repair

[Emantan]

I had my iPhone 4G screen repaired, and since have not been able to get service (I have tried all the tips from Apple's website). Has anyone had this issue before? Any advice, or know if it is a problem with phone or coverage?

***Edited to add labels***

[Wufai]

Who repaired the phone for you? Apple? 3rd party? Was it a repair or replacement? Is there any reception bars at all? (ie, not connected to Fido but still can use 911?)

I'm guessing the antannea connection is damaged or they replaced you a locked phone from another carrier. But without further info its all guesswork.

[Emantan]

It was done by 3rd party., but the phone was not replaced. Going to take it back to shop where reapirs were done