inappropriate order closing

I am very disappointed with this broker's service. I experienced a very unreasonable difference in order closing prices. I closed the Buy position at the price of 2677.11, but the broker actually closed it at the price of 2676.77, even though market conditions at that time were stable without significant fluctuations. This caused my balance to decrease unfairly to the point of experiencing losses. When I submitted a complaint and included evidence, my complaint was ignored and only given general reasons such as slippage, without any attempt to explain or prove the matter in detail. As a broker that claims to use a Market Execution system, transparency and accuracy in price execution are very important. However, this experience shows indications of practices that are detrimental to customers. I do not recommend this broker to anyone. If you prioritize honesty and transparency, you should look for another broker who is more trustworthy.