Why is my phone randomly shutting down frequently with an Android System error?

[AC Question]

I am currently running Android Lollipop 5.1 on my HTC one E9+. Recently, I noticed my phone keeps frequently shutting down with an error showing Android System error. I tried restoring my phone to the factory setting Android Lollipop 5.0 it worked fine but after upgrading it to 5.1 the error keeps showing up. Could you please help me out?

 

[dpham00]

If a factory data reset doesn't help then I would return it to htc for a warranty replacement