Hello. I have a problem with the Samsung GALAXY SII mobile phone. Yesterday, the cell phone pedaled normally. I turned on Messenger this morning and my cell phone was down. It didn't respond to the touch or went off, so I was the last to remove the battery. When I put the battery back and tried to turn it on, nothing. The mobile phone does not respond at all. Even if I plug in the charger, the cell phone won't start at all. Can someone please advise me what's wrong? What fault? Thanks.