German Market – missing post number

Hi, I use both plugins “German Market” and “DHL for WooCommerce”. A customer has entered a Packstation as the delivery address and added her post number in the address line 2 field. When I try to create a DHL label, I get the error message “Post Number is missing, it is mandatory for “Packstation” delivery”.
Can you please tell me what I have to do? I had already searched for solutions, but only found those for the Germanized plugin, which I unfortunately could not adapt. Thank you!