To connect with Vergelijk.nl API and to fetch daily costs of your ads, you'll need to connect your Adcurve account to the Vergelijk cost API.
Please follow below steps and establish your connection.
Login with your Vergelijk.nl login credentials at the following URL:
Select your account, go to the overview page and click on the button for "Clicks & Cost API"
Find your Verglijk.nl cost API Token and copy/paste the API token into the Adcurve wizard to establish the connection.