Incidentally, no time control with an addition per move is actually blitz. (Chess.com is confused about a lot of things.) A 30 move game becomes 7 1/2 minutes each whereas a 60 move game is 10 mins each; but you can't actually lose on time if you don't want to. So it isn't blitz.
But it's still too fast for you to learn from. Around 1200 rating they all try to play non-openings and just win on time. It can be hard to get out of the 1200 to 1375 bracket but once you do, your opponents will be much better players and often trying to play well rather than winning on time. You have to learn openings at that stage. It's no good believing the people who claim that openings don't matter below 2900 or whatever. Most games are probably lost through bad opening play. You get into a bad position and never recover.


I just can't get better I hover around the same rating constantly and I don't know why.
I can tell you why.
It's because in order to be able to learn by playing blitz, you already have to be a good player.