If the TV cannot load YouTube successfully, here are some methods for you to do the troubleshooting:
1. Check whether YouTube is the latest version. If not, uninstall it and upgrade it to the latest version.
2. Check the Time and Date on the TV.
3. If Time and Date are correct, please try to update the software of the TV online.
4. If the Time and Date are incorrect, please try to correct the Time and Date and load Youtube again.
If the issue cannot be resolved, please report it to the after-sales service, or please feel free to call the TCL hotline for further help.