problem with authentication server

Hi! My customer just ask me about this and i stuck with this. my english may not good. 

my customer use Ldap to take user form AD.

this is my policy of my customer:

1/ sales 1, sales 2 want to go internet, thay have to login user and password

2/ Ceo and Admin go to internet by using MAC. but they don't have to login user and password

This is my problem. when i active 2 policy at the same time. Ceo and Admin go to internet and they have to login user and password. But when i deactive 2 policy, they work as normal 

This is my customer network model : Server -> Core Switch -> Fortigate

Please help me with this. thanks you!!!