Recon.accnts &1 and &2 do not match, open item cannot be cleared

What causes this issue?

A clearing cannot be processed because the system determined that the
reconciliation accounts used do not match. This can happen when a change
is made to the reconciliation account in the business partner master
data.

System Response

The posting is rejected because follow-up processes such as reset
clearing would not be possible.

How to fix this error?

Correct the mapping or correct the documents to be cleared. Make sure
that the reconciliation accounts referenced within one clearing document
line item are consistent.

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.