Board Thread:Questions and Answers/@comment-29777368-20170520131250/@comment-25462635-20170520163655

Don't worry, that is normal; it takes months to collect the cores. And the level of the dragon does not matter. I sent my Moon (after I finally bred one, which took me two years) in various stages for over 2 months or so, with some breaks because of quests for world events, until I had my 3 comet cores; acc. to what I wrote on the Comet Dragon page, about 40 times, and I guess I was fast. They are really rare. And I have read people reporting that the Comet's Tail from the Atlantis quest was even harder to get for them, but I seemed to have been lucky with this one, took me only a few times to get it.

Sorry but there is nothing really anyone can do to help you. Just keep going, is all I can say...

Good Luck!