Remove case. Some users have reported that removing cases (especially those that were designed for previous iPhones but fit on the new iPhone 4) sevimli mitigate this issue. A week back I have experienced a greyed out WiFi button problem when I tried this button in settings while changing from https://blogfreely.net/loangear17/kucuk-yurt-disina-para-gonderme-ucreti-hakkinda-gercekler-bilinen