arc call fail

Hi all - I'm struggling with the alarm system in our new house. The old owners obviously had ARC monitoring previously, which expired. The alarm was setting and unsetting fine for a while. Now when I unset it at the front door the LCD says 'ARC call fail' and emits two bleeps followed by two...

Please can anyone help. I have a Pyronix Euro 46 Alarm with a gprs + sim module. After the free year of the Home Controll app, I changed the communication setting to just sms signalling. Everything was working fine until about 3 weeks ago. I was getting a test text every week. That stopped and I...