I placed an order, but for some reason my order was not accepted, despite the fact that I can see that the cheaper Buy Orders have already been processed. Why?
All orders are accepted only by users of the exchange, the administration of the site does not accept, control or interfere with trading on the exchange. If you want to speed it up, you can cancel the open Order and submit a new order with a more competitive price.
This is how most of all exchanges work, it is a smooth mechanism.