To get monitoring your system would need to be a DSC PC1616/PC1832/PC1864 V4.2 or higher, with an Alarm.com SEM installed. The SEM contains the cellular communicator needed to register your account and connect to our service. A guide on compatibility and installing the Alarm.com SEM 300 is linked below:
The issue you are describing sounds very much like the resistance is borderline high or wiring is loose somewhere. Double check to make sure no sensor wires were knocked loose during installation or the Eyezon module. Wire quality isn’t always uniform and older wires can be brittle where exposed.