My Huawei P8 Lite running on EMUI3.1 with Android Lollipop 5.0.2 connects to WiFi only after it is unlocked after more than 5-10 minutes of locked state. Happens with my other phone, Samsung Galaxy Young, too. It started happening some time after my local network provider installed a new router (D-Link DIR-803) for free. My Huawei is 1 day old while my Samsung is 2 years old. Any help is appreciated! 
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