I looked at your last few losses... you're playing 15|10 time control but finishing the games with over 15 minutes on your clock... you're giving yourself a huge time handicap. In one of your games your opponent finished with only 41 seconds!
If you want to play fast, that's fine. Fast games are fun. Select 5|0 or 3|0 and enjoy.
From bottom to top, everyone plays very precisely. They never hang a piece or never miss a tactic.
On the other hand i play exactly how i'm supposed to play. I blunder, leave hanging pieces and miss tactics.
Even a 1100 plays better than me. I started to hate this game. Why anyone doesn't make any mistake but just me.