¿What is it the percentage of profit or loss on Binance margin trade? How is it calculated for traders?

According to my experience in margin, the house always wins, since I use margin on several occasions to experiment and end up losing 90% of my capital, what I did realize is that binance keeps a large part of the profit, BECAUSE DO I BELIEVE THIS? I put $ 200 in margin and at the exchange they lent me 2000 usdt plus the $ 200 that is my capital was a total of $ 2200, my investment put it in the BNB / USDT pair I bought the BNB at $ 512 and sold at 522 $.

This means that I bought 2,200 / 512 = 4,296 BNB and I sold at 522 * 4,296 = 2,242.96, which in theory gave me a profit of $ 42, but the reality is that, when I paid the loan, I had only earned $ 4.2.

Then I made another loan I had the same $ 2,200 again and bought BNB at $ 518 but the currency had a sudden drop and reached $ 497 I received a message first on the phone saying that the losses in margin were high, but instantly it came to me Another message that they had canceled my orders to prevent me from going bankrupt.

So my question is:

When I invested the first time in the BNB / USDT pair, the BNB went up $ 20 and my profit in theory was 42 but I received only $ 4.2 when I paid off the loan; So where is the remaining $ 37.8?

My second investment I invested in the BNB / USDT pair and the currency had a fall of $ 21 and automatically binance canceled my orders and I lost half of my money only reflected $ 100 in my balance, now I ask myself another question; When I win the 42 and received only $ 4.2 it is not supposed that if the coin goes under $ 21 it should not lose $ 4.5; So where is my other $ 95.5?

There have been up to two times I had borrowed given USDT of 500 with 0% by binance in the reward center. In one of those times, I claimed it but could not see it any where in my margin wallet, so I didn't do anything with. Though I didn't know how to trade there. When next I am given, how do claim it successfully to see it for trades?

The reward that binance gives to use it in margin will never be reflected in the balance since the function of that reward is to pay commissions that each operation you do in magin carries, which means that each operation that binance makes charges you 0.01 % of the amount you are trading. With the 500 USDT you will pay those commissions that will not be deducted from your real balance.

NOTE: Operating in margín is risky, you have 80% of losing your money if you do not know how it works since I made the mistake of operating there without knowing much about magín loans.

In conclusion, in margín binance operates with your money they will never have a loss with your operations, the loss will come out of your pocket, but binance if it takes a large part of your profits, advice do not use margín.