Hello Shilpa,
While Delphix management service is in maintenance mode, you can login into Delphix Engine command line using sysadmin user.
Please try to login into Delphix Engine Command line as sysadmin user either using ssh or from VM console.
ssh sysadmin@delphixengineip
OR (from VM console)
sysadmin@SYSTEM
(Default password is sysadmin, unless you change it while configuring the engine)
Then follow the below steps:
delphixengineip > system restart
delphixengineip system restart *> commit
Restarting the management service. The current session will be re-established once the "service is available.
This step will try to restart Delphix management service which is in maintenanace mode.