Please check the Offer feed and Product feed error reports in your Cdiscount account. There you can see what needs to be fixed.

Check Offer error report in your Cdiscount account and fix errors

The CSV Offer feed error report is not possible to download after pressing the Download button. There is the "File not found" error.

The Offer feed is not accepted by the Cdiscount marketplace. The Cdiscount Offer feed mandatory value is missing for some of your products. All mandatory attribute values have to be filled for all your items listed in the Cdiscount Offer feed.

For more information about how to set up your Cdiscount Offer feed, please check:

Check Product error report in your Cdiscount account and fix errors