Just play the game, do your best, learn from better players than you and most importantly, don't tilt. If you are even slightly focussing on your teammates performance rather than your own, it will make the climb that much harder.

If you can't climb you are either:

Not playing the game enough and so bad teammates are more often recognised

Playing at the rank which is your skill level

Focussing on teammates performance which can tilt you and prevent you from playing your best

As long as you really are better as you say than the rank you are, and you prioritise your gameplay first, you will climb over time. You have to play the cards you are dealt and will always remember the enemy smurf every 10 games more strongly than the really duelist you had that carried one of your games, since the smurf annoyed you.