If other people can, you should be able to too if you have what it takes. Unfortunately you're not as good as you think and it wont change anytime soon if you dont realize it, analyze your mistakes, exploit enemy mistakes and improve your own gameplay.
Think about smurfs, why smurfs can easily climb in the same bracket you're having problems and get to higher ranks in any mode? Because they're really good for the bracket they're playing. If you were good for your bracket like you're claiming, you would be climbing too.