The data_engine was working and status changed to a failed state (displayed with red status). Deactivating and activating the data_engine probe does not resolve the problem.
Data_engine authentication to the Oracle instance fails and captures the following error in the data_engine.log
de: Oracle_Database::OpenDB OCIEnvNlsCreate...
de:  - Oracle_Database::OpenDB  status: -1
OCI_ERROR - ORA-28001: the password has expired
Make sure that the designated oracle user configured in the data_engine probe is not in password locked out state.