Major disappointment

This week when the system went from "Lollypop" to "Marshmallow", what ever that means, it did several evil things to my phone including erasing all of my photos and voice mails. After spending over six hours on my land line with technical support people from the service provider, LG, Android and Google, I came to realize that the photos are gone for good. I now am stuck with a very expensive phone that I can no longer trust using an operating system that is totally unreliable. With every "Customer Support" person I encountered I expressed how disappointed I was with the LG G4 phone and the Marshmallow operating system. I requested an upgrade to something more reliable and dependable. While the phone is still under its initial warranty, they would not replace it with a more dependable model. The warranty is worthless and I am profoundly disappointed with every step of the process of trying to get anyone to repair or replace my phone and make me whole. A truly terrible experience.