Why can’t I win a single ranked match?

I understand that maybe I’m not the best at the game but ever since I did my placement matches, (2 losses and 2 I had to leave unfortunately), I literally haven’t been able to win. Like I placed at only about 3,500 Rank Score and now after what feels like 20 matches I’m at 1,730. Only made it to the second round once only for my one of teammates to leave and then we lost. And I’m being matched with opponents who are at like 9,000 RS! Genuinely how am I supposed to win?!? Even if I’m the best on my team I can’t compensate for two bad teammates. Am I cursed? Is solo queue just this bad? It’s honestly making it hard to enjoy the game and again I’m not that good at the game but Jesus Christ why can’t I make a single point of progress?!? I’m almost half of what my original RS placement was?!? And that’s after I lost all the placement matches!?! I have more fun playing in normal cash out because I actually get better matchmaking somehow. I keep getting trash teammates, my opponents are cracked, and every time I’m even close to getting to the second round something goes wrong! I’m sorry for the yap and crash out, but I’m legitimately gonna smash my screen if I ever play another match. I’m just gonna play Power Shift because it doesn’t make me turn into a neurotic feral chimpanzee.