Differential invoicing: currency change not allowed

What causes this issue?

The currency entered in the IDoc or the SOA message (&V1&) does not
match the currency of the previously posted preceding invoice (&V2&).
You cannot change the currency.

System Response

The system cannot post the document.

How to fix this error?

Either deactivate the credit memo amount check for your partner in
Customizing for <LS>Materials Management</>, under <LS>Logistics Invoice
Verification</> -> <LS>EDI</> -> <DS:SIMG.OLMROMRY>Enter Program
Parameters</> or ask your supplier to correct the currency of the
invoice in question in the credit memo item of the IDoc or SOA message.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.