The HD2500, released in April 2012, only supports IR remotes, it does not support either the Bluetooth or Wi-Fi direct remotes.
For the IR remote, make sure no batteries leaked inside it. If so, clean the battery contacts. I had one old IR remote where leader batteries actually damaged the board.
See if you can fix the IR remote of find another.
That device is probably not worth much effort. with the 400 MHz CPU, it will be painfully slow and will not support Netflix profiles or the Amazon Prime channel. Unless you have a specific few older channels that you need, the device will probably be. disappointment.