Meizu signal problem

hi… i just bought meizu m2 note…the last days i have a terrible bug or something else …
sometimes when i receive or make a call the phone line closes after 5-10 seconds…Is anyone else withe the same problem?
Thx in advance!
my filmware is


@harris_par best is to switch to the A firmware as the U firmware was not designed for non-chinese.

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