Why did my phone suddenly close?

 Try to follow the next steps If the phone does not work, the problem is with the battery, you have to replace a new battery But if it works, follow the next steps First check the date Go to the cleaning program, improve the phone Then try playing YouTube If it doesn't work, go to Settings> Applications and notifications> Application information> YouTube {Force stop, clear storage timer, clear data} Then try using the program If it doesn't work Do factory restoration work by a person specialized in phone maintenance Then install the programs all over again If it doesn't work The phone is damaged and needs a telephone engineer