I tried flashing phones with various site bundles and always have prl issue with my verizon 4 running on 6.1.2

Sometimes my phones starts giving problem. Sometimes when i leave my city, my phone has network but if somebody calls me my phone shows switch off and i also have problem in recieving message and calls when i was out of my city. So this is a serious issue of prl. I tries 3 prl for my phone but all fails to solve this problem.

Need guidance for this if neede to change some settings in plist file or if anybody have bundles for reliance plz contact me or give guidance here