I have a Samsung QLED TV, model QN85Q70AAFXZA. I've had it for a few years and everything's worked fine. Now, with no other changes, the volume button has stopped working on the remote; I can neither raise nor lower the volume, which I unfortunately set to 10 this morning, so it's lower than I'd prefer if it has to be stuck at something. All other buttons and functions work exactly as normal. There's no feeling of damage to the button, and it doesn't matter if I hold the raise or lower volume button for a while, or if I press more firmly. The TV has all the latest updates, and the self diagnosis says the tv is fine. The remote control is fully charged. The remote control is the one that came with the TV, and the remote control model number appears to be RMCSPA1EP1 - it's the solar-powered version. The sound output still works, and it's the standard TV speaker. Any thoughts?