Connection reset with FPAM web launching sessions

Hi,

I recently implemented FPAM and I have a strange behavior with all the web launching sessions.

The FPAM is in a subnet dedicated.

My pc is on another subnet and the internal services and external(obviously) are on other subnets.

In the middle there’s a Fortigate.

I have also an ACL for deny the traffic to the internal services from my pc, so I must traverse the FPAM to reach the services.

I launch multiple web launching sessions to multiple sites internal and external and after so much time, I can’t define how much, I receive some ERR_CONNECTION_TIMED_OUT from random sites.

If I try to reopen the site, I can no longer access it; I have to wait a long time before it starts working again.

From what I've gathered so far, connections are more stable if I use the site's IP address directly instead of the FQDN, but sometimes are slowly(
But at least they don't time out.)

When I have the reset, the FPAM is capable of ping and resolve the destination internal or external site, seems to be a problem of DNS/Forticlient agent/Browser, i don’t know..

Do you have any idea what it could be?