Oracle Solution for Error ora-31523

ORA-31523: could not find change source string for CDC change set string

What triggered the Error:

The change source was missing for an imported Change Data Capture change set.

What should we do to fix it:

Drop the imported change set because it is invalid. Verify that the schema containing the missing change source was included in the original export. If needed, perform the export again, including the schema of the missing change source.