This article explains how to allow the administrator account to access the system quarantineSolution
The administrator profile must have at least read/write access to “System Quarantine”.
System > Administrator > Access Profile
In FortiMail 5.3.0 an additional step is now required for this administrator to manage the system quarantine. The account has to be defined as “Member” in the system quarantine folder settings.
AntiSpam > Quarantine > System Quarantine Setting
Edit the system quarantine folder the administrator should have access to and define this account as member: