
Cancellation is not possible; cancel target documents first
You have tried to cancel a document that had been copied to other marketing documents. In other words, the document you try to cancel is not the last document in at least one marketing document chain.
Cancel all the target documents first. Documents in the same document chain must be canceled sequentially starting from the last one.
For example, a delivery is copied to an A/R invoice, and the A/R invoice is then copied to an A/R credit memo. You must cancel the A/R credit memo and then the A/R invoice before you can cancel the delivery.