add_media_server_on_clients not adding all media servers

Configured media servers on bp.conf (master server ms48)
MEDIA_SERVER = ms11
MEDIA_SERVER = ms31

After running add_media_server_on_clients only 1 media server was added on clients:

Client bp.conf example: 
SERVER = ms48
SERVER = ms11
MEDIA_SERVER = ms11

Media server ms31 is not added. Re running the script marked the following message for all clients:
root@ms48 # /usr/openv/netbackup/bin/add_media_server_on_clients 
Updating client xx
No update of client xx needed
Updating client xy
No update of client xy needed
....

I'll really appreciate your help.

Thanks