Charging for additional call outs - *******

I have been with Chubb originally and now with National. My alarm is monitored and I pay monthly. In the past month, I had a problem with my alarm (which was fixed) but it meant it went off more than 3 times DURING the MONTH. I have now been charged an additional call out FEE!!! This is outrageous, most months I never have any call outs, yet the one month I have a problem Im penalised!!!