Here we would like to draw your attention to OMR9 transaction code in SAP. As we know it is being used in the SAP MM-IV (Invoice Verification in MM) component which is coming under MM module (Material Management).OMR9 is a transaction code used for C RM-MAT MR Payment Block Reasons in SAP.
It comes under the package MR0C.
Transaction OMR9 technical data table
|Purpose||C RM-MAT MR Payment Block Reasons|