@WhiskAppIssue91, you should contact TCL while it's still under warranty (which is through them, not Roku).
Where can I get support for my Roku TV™? | Official Roku Support
This worked for me and I hope it will work for others...
Using your Roku remote,
1. Press the home button.
2, Go to Settings > Display type, and select "4K HDR 60fps TV. (There were some messages I ignored.)
3. Press the home button and go back into Fubo
No more split-second flicker for me! 🙂 Hope you get the same results.
I went into my roku settings and changed the automatic refresh rate to off and it fixed all the flickering