I am traveling now. My original battery had problems, so I brought 2 replacement batteries with me. I bought them at Amazon and They worked fine for a long time before the travel. Since I lost its charger in one hotel two weeks ago, I just used my phone to charge both batteries every night. It worked fine until yesterday. It suddenly restarted my phone every 30-60 seconds. I changed to another battery, it was the same, so I believe it was the phone. The battery still can be charged no problem. I remember a few days ago, my phone got a notice saying it had virus and it would damage the battery soon, so I had to download an app to clean the virus. I was in a bus visiting fjord without wifi and my connection was not very good, so I could not really download anything. In addition, I was not sure that was a scum to make me to download virus or spyware to my phone, so I turned off my phone and ignored it. For the last couple days, there were no problem. Now my phone restart every few seconds, which does not give me enough time to do anything. I can not download a virus cleaning app, or uninstall any apps. So what can I do?