It may happen if you have a pending Stop-Loss (SL) or an exit order already. With an already pending stop-loss or exit order, you will need extra funds to be able to place a duplicate SL/exit order. If you do not have this extra fund in your account, then your duplicate exit order will get rejected. That’s why we inform you while exiting if there’s a Pending SL/exit order against a position, to avoid any duplicate orders and rejections.