Users access To internet but Fortigate Not Access Internet

hi

i Have Fortigate on Edge and I Set Address Private ON WAN. And i Set Pool on link WAN (IP Public)

Users to Access internet used NAT POOL And not problem

but Fortigate itself not access to internet

i have set Loopback Interface and set Policy for Access to internet and NAT to Address Public but fortigate do not access to internet