Do you have the showtime app? Just a guess but that might be having issues.
I had the same issue. Uninstalling the Showtime app worked for me.
Disable the showtime app
Mine doing the same, will remove Showtime app and advise.
That panel looks horrible
https://reddit.com/r/bravia/comments/9tp68r/what_is_this/
Could you post a little less detail. That will help us diagnose.
Do you have the showtime app? Just a guess but that might be having issues.