Same result with two different remotes? That would certainly point to the Express. I assume you've restarted/rebooted the Express at some point. If you're using the TV's USB port to power the Express try the supplied power adapter. If you have another HDMI cable you can try, do that. Do you have another TV you can try it on? Just trying to cover all the bases.
You could use the Roku app on your phone/tablet as a remote. I don't like a remote without physical buttons, but some people seem to like it.
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