expiration_timeout_minutes defines how long time, the user have to initiate agreement acceptance. Specifically, when they will directed to our landing page. It does not affect the timer they see after they have entered their phone number on our landing page. The timer is always set to 5 minutes, and it starts as soon as the user enters the phone number and clicks "Fortsæt".
It is actually the time, they have to swipe in the MobilePay app. Which happens right after they click "Fortsæt", because this initiates the push notification to the app. So if you set expiration to 30 minutes, the user have 30 minutes from when you create the agreement until they must have clicked "Fortsæt" and swiped in the app.