In order to Disarm the Gen 2 Alarm System, you will need to create a 'voice code' in the Alexa app . The voice code is a 4 digit number that you need to setup in the Alexa app. You can use a User code that you have already setup in the Alarm Panel.
How to create voice code:
- Open the Alexa app and select 'Devices' tab at the bottom of the screen.  
- Select the Gen 2 Alarm System device
 In this example it has been renamed to 'Office Alarm' 
- Select the device 'Settings' at the top right 
- Turn on 'Enable Disarm'  you will see this message display.  .   
- Select 'Ok' if you agree.
- Now create your 4 digit access code 
 Note. The voice code can be the same or different from your alarm display. 
- Enter your 4 digit access code again to confirm.
- Enable 'Disarm' should now be enabled and you can now disarm the Gen 2 with your voice.  You can Select the back button or exit Alexa 
- Test out the Alexa Disarm function by arming your alarm panel
- Now you can say 'Alex Disarm', Alexa will then ask for the name of you device.  In this case we have named the Gen 2 device 'Office Alarm'
 or
 You can simply say 'Alexa Disarm Office Alarm (Again, say whichever name you named your device)'
- Alexa will then ask you for the voice code. When you give Alexa the voice code, the alarm panel will then Disarm.
How to create a routine in the Alexa App to Arm Away or Arm Home
https://osigodirect.kb.help/how-to-create-a-routine-in-the-alexa-app-to-arm-away-or-arm-home/
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