Chosen Solution
I can turn on my phone charge it all the basics, but only when it is connected to power. When I take it off from the power source, it just randomly restarts itself. I tried to soft restart it, and nothing has changed.
The issue is most likely from the battery gone faulty. Either replace the battery yourself, take it to a mobile phone repair shop or Last resort take it to apple to get battery replaced (most expensive option). Here is the guide on how to replace the battery and where you can buy one from iFixit: iPhone 6 Plus Battery Replacement iPhone 6 Plus Battery
Jeffrey, The phone probably needs a new battery. You can follow this guide: iPhone 6 Plus Battery Replacement And use this kit: iPhone 6 Plus Battery Hope this helps, Charlie
