Zoho Desk - Make main lookup - account rather than contact

Zoho Desk - Make main lookup - account rather than contact

I have created a new layout in Zoho Desk. However I want the main lookup for the ticket to be the account and not the contact. How do i change this?

We have created this layout to deal with track our interal upgrades of our customers software, so we want to link the ticket to the account but not a specific contact