Text position in Outbound Delivery Request - no reference

Morning experts,

I'm a little bit confused at the moment:

I have a delivery note in ERP system, X positions, for Spain

When this dnote is distributed to EWM, it automatically gets an extra text position, without any reference to ERP document:

As you can see position is completly empty, no reference, ...

This happens only for Spain orders, thought maybe somtehing wrong with the customer/business partner, but can't find anything different to "normal" customers.

Any ideas what can happen here?

Thanks

Michael