If the phone button does not work, it is recommended that you:
1. If you cannot use the return key to return to the previous screen or exit when running a program, you are advised to click the HOME key to return to the standby screen and try to enter the program again.
2. Shut down the phone and restart it.
3. If the Back button, menu button, recent application button, or HOME button of the mobile phone cannot be used, uninstall and delete the recently installed software.
4. If no, back up the data (such as contacts and pictures) in the phone and restore the phone to factory Settings. If the problem still exists, there may be a problem with the internal hardware, it is recommended that you bring the mobile phone three package voucher, send the mobile phone to the nearest Samsung service center for engineers to check the machine.
It depends on the model. One is integrated in the outside on the screen, belongs to this kind of return key block outside the screen quality problems, such as OPPO A59s a is independent of the return line, menu spirit return key block this kind of situation mostly break the return key, of course, there are a few small board, wiring, or motherboard problems. For example, OPPO R9\/9S