Kernrechtsfrage
Whether defective service of the payment order was absolutely void or merely voidable
Extrahierter Entscheid
The irregular service was not absolutely void; it was only voidable unless the payment order never reached the debtor at all.
Extrahierte Begründung
Swiss debt-enforcement law distinguishes between a completely missing service, which makes the proceeding null, and a defective service that can be cured by timely complaint or opposition after actual knowledge.