dns clustering sync

[asmar]

Hello,

I have a dns cluster with 3 server.
1 vps for ns1
1 vps for ns2
1 dedicated that holds the domains.

If I add any domain to the ns1 then all zones are ok. If I add a new domain on dedicated server then it does not sync with the ns1 and ns2 and domains are not working.
I have setup all the servers in the cluster to sync the zones.

Any help is much appreciated.

Thanks