Accessing HA secondary via MGMT link and OOB VDOM

Hello Engineers

i have 2 601F in HA cluster (Active/Standby).

There is a cable between the OOB-SW to each 601F into the MGMT port on the same VLAN.

i need to access the FortiGate directly , when connect my laptop to the Firewall Primary one in MGMT port i can ping and i can login via GUI ,

BUT, when connect my laptop to the Firewall Secondary one in MGMT port i can`t ping and i can`t login to the GUI also , when i connect my laptop to secondary firewall also disconnect the MGMT port on Primary Firewall .

the another issue is

yesterday, i upgrade the Firmware of firewalls in (HA Mode) when the Primary on reboots the Secondary become the Primary as well as but what i noticed it i can reach internet via VDOM " INTERNET "

BUT, Also i can`t Reach the MGMT IPs of the switches and servers in VDOM " OOB "

After the First firewall finish the Reboot it Becomes the Primary and the i Can Reach the MGMT IPs of the switches and servers.

So i think the issue is between the OOB Switch and the second Firewall

SO And advices to TSHOOT this issue ?

Thanks to all