Is it possible to be right next to a ship and not able to shoot it?

By Tiberius the Killer, in Star Wars: Armada Rules Questions

Played a game today, and I had my assault frigate almost touching a ISD. On my turn, part of the Star Destroyer was in my back arc, but I could not draw a line from my yellow dot to either his side or front arc's dots without crossing the his arc lines. We decided I couldn't shoot at all. Was this the correct decision? Thanks for your help!

Are you able to replicate the ship positions and take a photo?

If you couldnt draw yellow dot to yellow dot without crossing HIS hullzones. Then correct you cannot. This sometimes happens when only one hull zone is in arc and that hull zone is pointing away.