Advia is a Federal system
It may be under the influence of HIH Aisling Duval's Power structure but the controlling faction is the Latji Coalition, a Federation Confederacy
The Latji Coalition is currently in a war with anarchist Adiva Crimson Society, over who controls Advia, hence the Federal Naval patrols and interdictions.
If you had been supporting the Adiva Crimson Society, especially with the new CZ scenarios, and had lost Rep with the Latji Coalition until they were hostile, the Federal Naval patrols would see you as the enemy and attack post interdiction.