It sounds like the issue might be with your TV, especially since you're using a Roku Stick for streaming.
Here are the troubleshooting steps you may need to consider:
To start with, Try a different TV or plug the Roku stick into an alternative HDMI port. Additionally, please ensure that the Roku stick is securely connected to both the TV and the wall outlet.

Please try doing this and see if it helps with what you're experiencing.