Door Sensors Setting off Base Station When in Disarmed Mode/

I just installed a Ring Wireless Alarm system and was feeling so pleased with myself until I disarmed the system, opened the doors and the base station alarm sounded. I quickly closed the doors and tried it with other doors and the alarm sounded again.. Why are the sensors setting off the alarm when it's disarmed ? I can't seem to get the door sensors to disarm. Grateful for advice.