Not getting sufficient points to improve my elo


Playing against a person with a higher elo increases the rating you earn if you win, and decreases the rating you lose if you...lose.
For example, I'm just about 800. If I played against a 1200 and won, I'd probably get about 14 points if I won, and -2 if I lost. But if I played against a 400, I'd probably only get 2 points for winning, and -14 for losing.
On another note, the "review rating" is kind of iffy at times, so don't take it too seriously.

Ratings change is more complicated than what was said above.
There is also a major component that looks at the estimated accuracy of your rating, based on how much you play.
https://support.chess.com/en/articles/8566476-how-do-ratings-work-on-chess-com
The post game estimated ratings you cited have nothing to do with your real ratings. They are just there for fun--a kind of "guess the Elo" attempt.