In some rare cases when initially setting up the DDM web interface you may be presented with an error ‘The ddm already has an admin user’ when entering in the password (step 2/5).
If you see this message, please delete the DDM VM and create a new one. If you continue to experience this error contact Audinate Support through the Support Portal https://audinate.force.com/support/s/contactsupport
The issue is currently being investigated.