Don't know. Could be a problem with the remote. Could be a problem with the TV.
As that's not the remote that came with it, that means you bought it afterwards. If it's a brand new remote, take it back to the store from whence it was purchased, or better, exchange it. If the new one does the same, then it's probably a problem with the TV. If the new one works, well, you solved it.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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