Strange it doesn't work for me. :( I installed the Bol.com version, then after that I've got directed to Koongo, and have it installed that. The Bol.com version disappeared from my apps. And, with the new version while it was installed to my store, I was unable to do anything at all.
In this case, it seems you installed the specific BOL app and the General Koongo app afterwards, the general app installation deactivated the former BOL app installed. We can take care of your integration and reset your Trial period. Can you please get in touch with us at email@example.com? Thanks!