Sometimes Remarkety has trouble pulling information from PrestaShop because of internal store errors related to PrestaShop's code, PHP version or "display error" level.
To make it easier for us to track the problem and solve it for you, we may ask you to temporarily enable displaying errors in the webservice API. This will not effect your website browsing, but only the back-end API connection.
To do this, open up the file:
Around line 554, in the function setError(), right after this line:
$display_errors = true;
And contact Remarkety support team to let us know you've made this change. We can then help you figure out where the problem is.