When the images of your products are shown in an incorrect order on bol, it may be the case that the product information is either not processed correctly or bol has changed the image order itself.
Bol can import the order of images in a different way because of a couple of reasons. Sometimes this is done in the light of improving conversion, and sometimes it can depend on a type of category. This thus means that there might be a discrepancy in the order of your images which you set in your back office, compared to what is shown on the bol platform.
If you want to validate whether your product information is processed correctly, you can verify this by reading this article.