Auto-deleveraging (ADL)
Auto-deleveraging (ADL) is a futures exchange's last resort: when a liquidated position loses more than its margin and the insurance fund cannot cover it, the exchange closes part of profitable positions on the other side to make up the loss.
ADL is rare and happens in extreme moves. The positions closed first are usually those with the highest profit and leverage, ranked by the exchange; Binance and Bybit show your place in that queue as a small indicator next to the position. If you are deleveraged, part of your position is closed at the bankruptcy price of the liquidated trader, so you keep the profit up to that point but lose the rest of the move. It is not a fee and not a loss of your own money, only an early, forced exit.
Learn more: how to avoid liquidation and insurance fund.