Stock keeping/parallel units of measure &1/&2 and &3/&4 are different

What causes this issue?

The receiving material is not managed in the same units of measure (
&SYST-MSGV3&, &SYST-MSGV4&) as the issuing material (&SYST-MSGV1&,
&SYST-MSGV2&). It is only possible to transfer <ZK>Material to Material
</> if both materials are managed in the same valuation unit of measure.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Enter another material or cancel processing.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.