That appears to be an issue with the TV itself, more specifically, some PCB running the lower portion of the display panel.
Reboot it properly by turning off at the wall for a bit. I had that happen in the middle of the screen and thought it was hardware 6 months ago, did a hard reboot and not had it back since.
Exactly same problem happen on my old Bravia. Sony has changed it with a newer model.
Contact a local technician immediately. It will later occupy the entire screen with these type of lines
It's likely your panel and not the software