My resolution was changed and now screen is frozen on resolution mismatch. Change devices resolution. Screen frozen on this message
I assume this means it is not responding to any input from the remote.
Normally, I'd suggest doing a restart via Settings > System > System restart but if it's not accepting command from the remote, that won't work.
Try disconnecting the power connection to the device for a minute or so, then plug it back in and let it start back up. If you're lucky, the ability to control the unit will be restored.