Hit up XDA FORUMS and see if you want to try another ROM or image. I defer to XDA on the how to and more. But it's a last hurrah area so try it.
In parting, be sure to remove the SD Card and SIM from the phone, factory reset and try one last time.
Out of nowhere, my phone tried restarting, but its stuck on the "samsung galaxy s6. powered by android" screen. I cannot do anything other than hard reset it, which does nothing but turn the screen black and instantly put the boot up screen back on. I drained the battery by leaving it like this, and the second i plug it back in the same screen pops up. I tried all the power/home/volume button combinations and none of them worked. Any ideas?

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