If the cambioApp does not work, you can always reach us via the call center +32 2 505 40 40, available 24/7.
However, it is very important that your phone is sufficiently charged at the start of your reservation or that you take a charging cable with you. That way you can be really sure.
Also make sure you always have the latest app update installed if your smartphone is not accepting automatic updates. For most of you, the cambioApp updates automatically and you don't have to think about it at all.