Here are some steps you can take to resolve an issue with switching between channels on a Smart TV:

1. Check to see if the TV is connected to a separate set-top box.
2. Ensure your TV is connected to a strong and reliable WiFi signal.
3. Check that all of the TV's cables are firmly connected.
4. Try resetting the TV Remote Control or setting it up again.
5. Check and make sure that the TV is set to the correct antenna/source.
6. Try adjusting the picture settings on the TV.
7. Restart the TV, running a diagnostic (if available).