ORA-08704
Assertion is enabled but failed to validate existing data.
Cause
An assertion violation occurred when assertion validated existing data, the assertion state is set to ENABLE NOVALIDATE instead of ENABLE VALIDATE.
Action
Execute the ALTER ASSERTION VALIDATE DDL command for full validation. If the validation succeeds, the assertion will transition to the ENABLE VALIDATE state. If it fails, the assertion will remain in the ENABLE NOVALIDATE state.