How can i get rid of BELL TAMPER message on home alarm?

Hi guys, this is my first time on a forum like this. Our home alarm is showing a BELL TAMPER message so I cannot set the alarm. It is also displaying the message to call installer. have a user guide for Scantronic 9752 which I have looked through and it says the installer could have left the system be set so that the user can override some fault messages so that I can set the alarm but it doesn't look like I can. I have no idea about engineer codes or anything! can anyone help out so that someone clueless can follow their instructions or should I call the alarm company?

Saj
November 2016