Zulu, Softphone but not physical handset rings

Zulu has been setup on our freepbx system,
Have managed to connect my mobile to the phone using my extension, this however stops my deskphone from working.

Does the mobile need its own extension and use a group to ring both or can i get it to ring both with ext?

Restarting the desk phone makes that start ringing but the mobile stops.
Thanks

Edit,
Just found another post with answers, this sorted it for me.

What does Zulu have to do with your mobile phone?