Compellent SC4020 does not allow changing Fault Domain 0's IP

I cannot change Fault Domain 0's IP address once it has been set.
Nor can I remove Domain 0.
I can change Fault Domain 1's IP or create another Fault Domain.

The error message is:

"Summary: An error occurred trying to modify the PortGroup object (identified as ( 1 3 ))

Cause: Rollback Transport:PortGroup Request: 181530 Set Source: API Leader: 1 State: 7 CheckDeleteStatus RetVal: Failure Idx: 1 3"