Doc. type/item cat. &/& (requisition) <-> &/& (purch. order)

What causes this issue?

<GL:purchase_requisition>Purchase requisitions</> of
<GL:document_type>document_type</> &V1& or item category &V2& may not be
assigned to purchase orders of document type &V3& or item category &V4&.

How to fix this error?

INCLUDE EINGABE_PRUEFEN_NA LANGUAGE EN
INCLUDE SYSADMIN_NA LANGUAGE EN
The latter can make the necessary settings using the Implementation
Guide (IMG)
<DS:SIMG.SIMG_CFMENUOLMEOMEB>Define document types and number ranges
</>

Error message extract from SAP system. Copyright SAP SE.