We are currently using zoho desk to communicate with customers via tickets ( which are created by customer mails sent to us)

Moving ahead we are trying to figure out a way to use the Zoho desk for internal communications, for which we have created separate departments on the Zoho desk.

We need to disable/hide the Email and Contact field in Zoho Desk Ticket as when we are trying to create tickets against Lead, Deal in Zoho CRM it is populated using customer details in place of mail id and contact name, resulting in shooting a mail to the customer about internal communication. 

When we replace the email and contact with a different email, there is no ticket mapping with the respective lead or deal.

Is there a way to disable/hide the Email and Contact field in Zoho Desk Ticket Template for the internal department's communication?