Value &1 not contained in the master data table for &2

What causes this issue?

When subsequently reading the master data, a value was not found in the
master data table. Therefore, the corresponding attribute cannot be
filled either. This data record cannot be updated.

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?

Check the data you updated.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.