All the phone in the branch get the error "no park number available"

Please note that the call park numbers are node specific and you will need to specify a unique range for all the nodes. Its quite possible that the users for which it is not working does not have this configured for their respective CM server.

Regards

Deepak

I am not I fully understand . The phones and call park number assinged to the same sub . 

Is that what you meant ? 

The call park range is selected from the list of servers where the call originates. For example, if phone A (registered to node A) calls phone  B (registered to node B) and the phone B user presses Park, phone B requires a call park range in the CSS that resides on node A. In a multinode environment where phones and gateways communicate with various nodes and where calls that originate from any server may need to be parked, the phones require a CSS that contains call park ranges from all servers.

On the Call Park configuration page, you get the option of choosing the CM from the drop down, make sure you configure the unique range for all the CM servers in cluster.

Regards

Deepak

It unique number . 

Seems to be configured fine . 

Did you check if the phone had required CSS to reach the Call Park number range configured on the server from which the call is originating.

Regards

Deepak

Ok so now I realized it's not working to some of the branches .  

You can change the service parameters to make it so the ranges are clusterwide, and you don't need to define one range per node.

Hi,

As deepak suggested

1. Check that call park DNs are configured in each node in your CUCM cluster

2. Make sure that Branch Phones CSS can see the park DNs