While troubleshooting, you might be required to restart your TCL Roku TV.  Below are the step-by-step instructions:

1. Press  on your remote to open the main screen.
2. Scroll up or down and select Settings
3. Press the right arrow button and select System 
4. Press the right arrow button and select Power
5. Press the right arrow button and select System Restart
6. Press the right arrow button and select Restart
7. Press the   button to confirm 

Note:  It might take a few minutes before your TV restarts.