Invalid basicServiceCode for issuer
This error comes from PostNord and usually is typed like this for example:
PostNord: 19 is an invalid basicServiceCode for issuer Z14 from FI to SK
The error indicates that the shipping service you are trying to use for the shipment is not usable in the route you are trying to use it in. You must use a different shipping service for the shipment.
This error appears because you are trying to use a shipping service that is only usable from a specific account issuer(s); for example PostNord Sweden. This is also the reason why Packrooster can still find the pickup points for the shipment but the fulfillment does not work.