Alarm monitoring not calling phone

I've been crawling through all of the messages about monitoring alarms. I have had a series of tripped alarms over the last two weeks and not to receive a single call even though I have set up all of the emergency contacts properly in the software. Notwithstanding the fact that it never notifies my phone that there's an alarm going off, I'm also not getting the phone calls that I'm paying for through the monitoring service.We are in a low mobile signal area for the base station but today my phone was in a high signal area and I didn't receive a call to say that my alarm had gone off. Any ideas what this might be?