Hi @vincentste, welcome! A prepaid sim card is indeed pre-activated, which then gets confirmed when you first use it for a call or text after inserting it in the phone. However, for that to work, you need to be connected to a Dutch cell tower. With Maastricht being so close to the border it's possible you were instead on a Belgian tower. Can you try again, in an area near the middle of the city or something like that to be sure the tower is Dutch. If it doesn't work, either return to the store for manual activation. Or fill in your forum profile with both the phone number and the sim card number (both can go in the ‘mobiel klantnummer’ field) and reply here when you've done so. And then we will  check this and manually activate.