Assassins Creed Rouge pistol bug

Hello everyone! Help)) I love the Assassins series games. But I was faced with the fact that there is no second holster in the rogue, and accordingly there is no +2 pistol. The whole game has passed, all locations are open. But, unfortunately, I just can't add 2 more pistols to myself. XBOX 360 platform, not stitched. License disk.