First, if you don't already have a Roku account, go to roku.com and set one up with your chosen email address.
Then, do a factory reset on your tv to erase all its settings and set it up like it was a new set, and log into your roku account. I have separate Roku devices, not a Roku tv, so I don't know the menu path, but on my devices Factory reset would be under Settings > System
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600
If this post solves your problem please help others find this answer by clicking "Accept as Solution.". Please only do this if it ACTUALLY solves your problem.