looking at your replies on this thread, its 100% a mental and mindset issue. if you dont stop making excuses such as "i have good mechs already but i lose" "my team throw" "if i dont tilt im the goat" YOU WILL STAY HARDSTUCK.
Get an improvement mindset, stop tilting, stop crying and you will climb.
If your mechanics were significantly better than your rank, you'd be at least ascendant. If your game sense was good too, you'd be immortal, even solo qing. All the excuses will keep you stuck. Look at each aspect of your gameplay and fix them one by one, compare yourself to pro players, don't be delusional and cope.
Mental is the most important thing in ranked, if you tilt and make bad decisions because of it, you will stay hardstuck.