Mobile phone problem ... solved

I am writing this for my own benefit should the same problem occur in the future.

Today I was in Karmiel where I had meetings all day, so I set the phone to 'vibrate' and also used the AutoSMS app, which sends a message to anyone who tries to contact me. The phone was working at lunchtime because I could send WhatsApp messages. On the way home, I noticed that I couldn't unlock my phone: the lock screen would appear, I would enter the PIN which was accepted and then the screen would go blank. This happened time and time again.

The easy way to solve this would be to turn the phone off - but I couldn't achieve this. After reading the manual, I discovered why I couldn't turn the phone off: I was pressing the wrong buttons. There are three buttons on the right hand side of the phone, from top to bottom: volume up, volume down and power. In order to turn the phone off, one presses the power and volume down buttons for a few seconds (that is, the bottom two buttons on the right hand side).

Voila! I managed to turn the phone off. When I turned it back on, everything was working again. The first thing which I did was turn off the AutoSMS app - this might have been the cause of the problem.