Bluetooth keyboard disconnects

I have a rhaspberry pi 3 and just tried to pair my bluetooth keyboard. It connects and works but eventually it loses connection (if I turn it off, or maybe goes to sleep?). If I go back into the Network / Bluetooth menu I am able to reconnect. Is there something I need to do to allow it to automatically reconnect after it goes to sleep / power cycle the keyboard? Thanks in advance.

On most keyboards if they go to sleep (but their power switch is still on) all you need to do is press a key and wait a few seconds for it to reconnect. It’s the job of the keyboard to reconnect to OSMC not the other way around.