Captain Kidd's Treasure (Assassin's Creed 3)

I can't get parts from the map. First, I took 3 parts from One-Legged, for trinkets, and then I went through a sea task where you need to look for parts from the map. Passed 3, and then they are simply not on the map, and nothing happens. I went to One-Legged, he only demands trinkets. And I watched a video on YouTube, where all parts of the map are obtained from sea tasks.