Get a Shipment 500 with PDF label format (production)

Hi,

We're having issues while getting the details of shipments handled by our DHL carrier with negociated rates, in production environment (500 Internal Server Error).

The URL used is: https://api.easyship.com/shipment/v1/shipments/ESUS107836304?format=PDF&label=4x6

The label is available and can be retrieved by setting the "format" parameter value to "URL" or "PNG".

We're also getting a 500 error for the creation of those shipments when both "buy_label" and "buy_label_synchronous" parameters are set to true, and the same "printing_options" (format & label) are used.
I should add that, even with the 500 error, the shipment is created and confirmed (Label Ready) on our account.

Thank you