What the hell am I doing wrong????

Here’s the situation: I’m in silver 3 (duos) and constantly am trying to push for gold for a week or 2 now. I consistent hit div IV and every time I get there I drop back down to silver 3 Div 1. Almost every game my teammates afk or leaves after 1 goal (literally happened 2 times in a row). Now I’m not one to blame teammates but my luck is just bad.

I’ve studied all the things that should help me rank up, I’ve learned rotation, back post defence, reviewing games, dribbling and still every time I hit silver 3 div 4 I fall right back down. I feel miserable and I don’t know what I can do differently.

Any advice?