Its part of the experience as a bounty hunter. In my case, I have not been paid in half of the bounties I joined especially when I was new and joined any campaigns I find. But now im more particular in joining bounties and look deeply to the project and the team running it.
Yes It's true.For your first try and you get failed just try for how many times because I know there is a right timing for evrerything and I believe on that.