Will replacing the housing fix my antenna problem?

Hello guys. I have a iphone 6 which the cellular antenna stopped working. It just says searching, and after a while it comes up "no service". I have done all steps with the software, without luck.

I replaced the dock connector, and after that the cellular antenna worked, and i got signal. But after a while it stopped working again.

My frame is also really bent, i and i was watching ebay, where you could buy new frames with almost all the parts premounted. So i am asking for advice, if i replace the frame, with all the new parts, what are my odds of getting signal again? I don't have any other iphone 6 here, otherwise i could test the mainboard to see if that is broken or not. What do the more experienced guys here think?

Thank you!