mobile

A few days ago, I took the phone to my hand and realized, there is no mobile signal. Phone said only emergency calls. I tried to restart. Nothing changed.
Rom version:Lollipop 5.0
The other fonctions are working fine.

I Tried to send to guaranty, But I forgot at paranoid android and they said "İts couse of the stock rom." Then they give me phone back. but these were happening the device working with lollipop 5.0

Then I tried all of these:
-Hard reset
-Custom roms
-Many stock rom
-firefox and ubuntu os (firefox stuck on bootloader too and ubuntu is just alpha.)
-Modem(radio.img). Then this, the imei code erased.
-another sim card

So, now I have just 2 issue. How I fix the sim card problem? How I bring back the imei? I really need help guys. And sorry for my bad english..