Why I lose to much lower rated player ??

You lose to lower rated players because of cheating….I play much better against people rated 1600 to 1700 compared to 1200 to 1300. Now these lower ranked players seem to play out of their minds aka cheating. I don’t encounter cheating nearly as much with higher ratings.  Most people who respond with learn from your mistakes are clearly blind to the fact it is clear as day most of the players cheat at lower levels.  To sorta prove my point I went to lichess and intentionally set up an account that was used to cheat 100% of my games and wanted to see how fast I would get flagged and it was rather quickly. It was cool to see that the account was listed as a cheater and then you will only play against others who have done the same thing. I COULD NOT BELIEVE HOW MANY OTHERS WERE LISTED LOL.  So it is clearly a huge problem and honestly chess.com will never fix the issue because many of these people pay for the memberships so all you can do is block the individuals

You feel that you should never lose to a lower-rated player?

Then you should never win against a higher-rated player, correct? Never. Because that would require him to lose against a lower-rated player (you) which you feel should not happen?