Unable to add RD Virtualization host

Hi all

I got a problem to add the RD virtualization host.

I deployed RDS for test.
 -1 virtual RD Connection Broker (Windows Server 2012)
 -1 virtual RD Web Access (Windows Server 2012)
 -1 RD Virtualization host 1 (Windows Server 2012)

Then I created Pool managed collection. worked well.

But I add another RD virtualization host from RD Connection Broker is failed.
"Could not add the RD Connection Broker server to the TS Virtual Desktop Server settings on the RD Virtualization host 2"

I checked RDMS overview, there is RD Virtualization host 2. but I can't create collection or add virtual desktop.

I also checked event viewer, found some logs below,
(1) Error
  -Source:TerminalServices-SessionBroker
  -Event ID:1537
  -Description:
    VM host [RD Virtualization host 2] is not being added to the broker or not currently running.

(2) Error
  -Source:Rdms-UI
  -Event ID:8210
  -Description:
     [Collection Name]:provisioninig failed. Reason:

(3) Error
  -Source:TerminalServices-SessionBroker
  -Event ID:2056
  -Description: 
      The Remote Desktop Connection Broker server could not enumerate the targets for the provider named NULL from the database.
      Pooled virtual desktop collection name: NULL
      Error: Logon to the database failed

Any ideas?

Thanks!