I didn't have this happen on any of my Rokus when they received the Roku 10 update, but there have been lots of reports of this happening to others.
Re-configuring your remote for your TV should get you back in business.
Roku menu path:
Settings > Remotes & devices > Remotes > Remote (In use) > Set up remote for TV control ... then follow the prompts.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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Ultra 4800 | Streaming Stick 4K+ 3821 | TCL Roku TV 43S245/C107X