If the WLAN of the mobile phone is always disconnected, you can perform the following operations:The source of the network is unstable, it is recommended to replace the wireless network to try to exclude whether the wireless router is far away;The WiFi router connection is not good, please check the connection of the wireless router;Wireless router Settings or parameters are faulty, reset the router to see;Back up important data of the phone and restore the phone to factory Settings.If the above does not solve your problem, please take the purchase invoice, warranty card and mobile phone to the nearest OPPO customer service center for testing and processing.