HA - Change from active-active to active-passive - Problem

[KPS]

Hi!

I am using a FG200E-cluster in active-active mode on 5.4.5. One VDOM is in Transparent-Mode, one VDOM in NAT-Mode.

As I am having some trouble, i wanted to change mode to active-passive. Last night, I switched, but then, I had some very big problems:

- Changed to a/p on web-GUI of master-unit

--> I was not able to see the second unit again. HA-monitor did only show one system - waited 5 mins but no success.

--> switched back to a/a --> both units became primary (at the same time) because the "second-unit" was still configured to a/p. --> network-loop

--> changed both units manually to a/p --> system was online again.

Can you give me a hint, what I could try to get the system up in a/p mode?

Thank you for your help!

KPS