Main Screen Blocked


Feb 21, 2017
35
1
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#1
i have a problem since 3 updates.. sometimes, when i do a call to someone, when i touch on contact and the call starts, main screen go black and i cant unlock the phone.. i can unlock only when the call is finished! and a lot of time the mobile asks me to press BACK and UP VOLUME before to unlock... why and how can i fix it?