iPhone 6+ Screen Freezing and Unresponsive

Love my iPhone, this is probably my 6th one, but it is the worst one I have had. My first 6+ was replaced at the store about 6 weeks ago because the screen was unresponsive. Tap, Tap , Tap and nothing happens, frozen. Phone rings and you cannot answer. iMessage screen flickers, tap one app and a different one opens, phone turns off and on by itself. I've tried everything that was suggested both by Apple tech support over the phone and in the store. The advice I read on line mirrored that of Apple's attempted solutions. Resets, restore, etc. I also make sure to close all apps I use so as not to use up any memory that could make the phone choke, if that even makes a difference? I was finally offered a replacement and took it. This new phone is now doing the same thing. That tells me it is an inherent issue with the OS, which is up to date.

I am at a loss here. I cannot bring myself to switch to a different phone. Between iCloud, Photo Stream, Apple Music, a Macbook Air and two iMacs I am fully entrenched. Plus, when the phone works, I love it! SO... what's a guy to do? Has anyone experienced this and if so, what was the resolution.

Thanks!