If the battery was unplugged for an extended period of time then it probably drained most of the energy out of it. Unless you remove the battery or at least disconnect it you will still have a small residual drain. There are things in the Monty that work all the time. If it were me I'd check the condition of the battery. It would not surprise me that it was dead or at least had some serious damage done to it.
As I said you may want to do a search here about battery care and types. Lots of good info.