Have you checked the Antenna on the pellet boss? I move my MAK around quite a bit and have found that I occasionally need to tighten up the antenna. You can remove the batteries from the remote boos, but I don't think that will reset any internal programming.
Another thing you can try in order to reset everything is to actually unplug the MAK. When the MAK is turned off, the Boss Controller still has power going to it if it's plugged in. When you unplug and plug the MAK back in it resets everything.
Unplugging will reset the BT module, if you still have issues you may have lost the pairing somehow. There were instructions on this sent with your unit, if you need help contact me