You have to allow the app to locate you to see your position on the map, to recenter the map on your location and get the distance between you and the selected cash dispenser. 

For iOS: go to your smartphone's Settings, tap on the Payconiq by Bancontact app and give permission to share your location. 

For Android: go to your smartphone's Settings, tap ‘Apps’ and select ‘Payconiq by Bancontact’. Tap on 'Permissions' and give your permission to share your location there.