Glitchy Flickering Screen

My daughter owns a 32-inch Sanyo TV that I've had for quite some time, though I can't recall the exact date. Last night, my Wi-Fi connection was problematic, which affected the cameras. Once we resolved that issue, her TV functioned perfectly. However, today around 11 am, after we returned from my sister's house, she approached me and mentioned that her TV was glitching. The top section, just beneath the time display, has about five lines of color or something similar. Every few seconds, the screen freezes, shifts to a darker hue and then returns to normal. While it's not a significant issue, it's certainly irritating. I’m uncertain whether it's due to the Super Bowl background update or if her TV is simply too small to keep up with these changes. I’d like guidance on how to restore it to normal. I've already tried unplugging and replugging it. The system updated everything apart from the factory update, but I lack the time to test that, and I’d prefer not to re-enter all the passwords if it ends up not working.