To use mobile refuelling with a credit card or Q8 Liberty card, simply add this card to your list of available payment and fuel cards in the Q8 Smiles app. For debit card payments, you will always be automatically redirected to the installed Bancontact app or another payment app that has the Bancontact functionality. You do not need to change any settings in the apps to be able to use mobile refuelling. However, you will need an active payment card in these banking apps, of course. ;)