This is why it's a good idea to buy TVs from Costco. They have great warranties beyond the laughable manufacturers' warranties.
I made two mistakes with my most recent TV purchase. I didn't buy it from Costco and I bought a TCL Roku tv. Next TV I buy will be from Costco and will not be a TCL. If I had to do it again today I'd buy an LG or a Sony from Costco, not a TCL from Amazon.
The issue you are experiencing is related to hardware issue. Have you tried contacting TCL support yet to inquire further? I'd suggest starting there to see what options or suggestions they can provide. Each Roku TV manufacturer provides direct support for their products running the Roku OS.