I bought a Lumia 950 around January 2017, and everything worked perfectly (hardware wise) until May. My device began to randomly reboot/restart, and I could not place my finger on a cause or an app that could be responsible for the crash. I performed several hard resets but nothing was solved. So I began searching online in different forum threads. I came upon a mention about something related to faulty batteries, and one user proposed a solution that worked flawlessly for me. This involves placing paper sheets the size of the battery underneath it, and another one wrapped over the top side (opposite to contacts) before finally closing the back cover.
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