Diagnosis
You tried to directly check an unchecked delivery using transactionVL06U, VL10U or the single conversion in VL10UC. However checkeddeliveries of type &V1& should be created within the number rangeinterval &V2&.
The actual delivery number &V4& is not within this interval.

Procedure
Use the Check&Combine function within transaction VL10UC.
This deletes the unchecked delivery and creates a new checked deliverywith an appropriate number.