I’ve had the constant looping login and other problems the past few months…but today something changed!
I have version 2.714.091.
I was trying to solve buffering issues in Plex and found this info:
LG B7 OLED TV - Owners and Discussion Thread | Page 206 | AVForums (post #6178)
and this:
Not sure which one of these solved the problem with XPlay but it’s back to working 100%.
4K, HDR, the works.
Hope this helps some others 
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