1, if not installed:
Please confirm whether there is a telephone. At present, it is found that this kind of problem will occur when using Root mobile phone by using Kingroot and 360 super root tools in 360 security guards.
Solution:
Download the latest version of the software from official website or use HiSuite for mandatory upgrade.
In fact, forcibly upgrading the ROOT phone has additional risks, especially if the recovery model has been modified. You may not be able to recover through the above operations, so it is recommended that you pay at the service outlets. If you don't have a telephone, I suggest you take the purchase invoice to the service outlet for repair.
2. If installed:
Since most of these problems collected recently are caused by 360 software, I suggest you uninstall 360 software and restart your mobile phone to see if the problem is solved. (When the animation starts to appear after opening the above the fold, press and hold the volume down key to enter the safe mode, and uninstall 360 and other software in the safe mode. When entering Safe Mode, the words Safe Mode will be displayed in the lower left corner of the phone. If an SD card is inserted in the phone, it is recommended to try to pull it out. If the USB cable is connected, please unplug the USB cable and try.