Translating Verisure state attributes

Configuration
1

I have made an automation that all users receive a notification on there phone when the alarm status is changed.

If the alarm is disarmed I receive the message: "Alarm disarmed by user’.

But I want to translate to status to Dutch like this:
Disarmed = uitgeschakeld
armed_home = Ingeschakeld thuis
armed_away = Ingeschakeld weg

After some googling I tried this but it’s not working:

alias: TEST ALARM
description: ""
trigger:
  - platform: state
    entity_id:
      - alarm_control_panel.verisure_alarm
condition: []
action:
  - service: notify.notify
    data:
      message: >-
        Alarm {% if is_state_attr('alarm_control_panel.verisure_alarm', 'state',
        'armed_home') %} ingeschakeld thuis {% elif
        is_state_attr('alarm_control_panel.verisure_alarm', 'state',
        'armed_away') %} ingeschakeld weg {% elif
        is_state_attr('alarm_control_panel.verisure_alarm', 'state', 'disarmed') %}
        uitgeschakeld {% else %} error {% endif %}  door
        {{trigger.to_state.attributes.changed_by }}
      title: Verisure / Home Assistant
mode: single

Anyone who can help?

2 
alias: TEST ALARM
description: ""
trigger:
  - platform: state
    entity_id: alarm_control_panel.verisure_alarm
condition: []
action:
  - variables:
      alarm_states:
        armed_home: 'ingeschakeld thuis'
        armed_away: 'ingeschakeld weg'
        disarmed: 'uitgeschakeld'
  - service: notify.notify
    data:
      message: >-
        Alarm {{ alarm_states.get(states('alarm_control_panel.verisure_alarm'), 'error') }} door {{trigger.to_state.attributes.changed_by }}
      title: Verisure / Home Assistant
mode: single

The mistake in your version is that this is an invalid use of the is_state_attr() function:

is_state_attr('alarm_control_panel.verisure_alarm', 'state', 'armed_home')

It should be this:

is_state('alarm_control_panel.verisure_alarm', 'armed_home')