Problems with Cifford Concept 300?

I have just bought a Mitsubushi GTO and it has a Clifford Concept 300 alarm fitted, the problem I have is that when you switch alarm off, like you want to clean the car inside out it resets itself and after about 5 - 10 mins the alarm goes off so you have to keep on resetting it, which is abit of a pain. Is there anything can do so as to when alarm is off it doesn't reset until you reactivate it