Connection time problem P7000

Hello everyone.
I am writing here after a very troublesome worries.

Here is my great P7000 walking I try several Roma with several fashion (flashtools, TWRP, ect) But I have noticed since two or three days when I activate my sim (airplane mode turns off the phone or restart) my network clings after 2 minutes! In short every time I lose I ba networks or I cut nothing for 2 minutes ...

But is most strange is that if I put a new sim card first hangs in his three seconds and asks me to configure it if I restart with the same card behind, his hands hanging 2 minutes.
If I deliver my sim card like its hanging behind her in three seconds, then restart or airplane mode, bam 2 minutes> <

I finished my flash by phone with the latest official ROM via flashtools but always the same.

If anyone has a solution I'm interested lol

(sorry for my bad english language)