Sales organizations deviate from each other. &1 and/or &2 (reference)

What causes this issue?

The sales organization of the reference document is not the same as the
sales organization of the target document.

How to fix this error?

If you want to add to an existing document by referring to another
document, select a reference document with the same sales organization
as the target document.
If you want to create a new document by referring to a document, make
certain that the sales organization and the document number are correct.

Error message extract from SAP system. Copyright SAP SE.