How Do I Fix My Oppo Won T Turn On. Your phone might have bootloop caused by software problem and it could be solve by hard reset. Plug the charger into a wall outlet.

Check that your outlet is working. Or you can use the original USB code to charge your phone by connecting it to your laptop. Check for Black Screen issue.
When Oppo logo is displayed release the key On.
To check if this is the case you will have to start the phone in Safe Mode as only the pre-installed apps are allowed to run in this mode. Black screen or does not turn on. Wait for sometime maybe the problem will be the draining of battery. The battery is faulty.
