Why does the order close automatically when I open a locked position on an instrument in MT5?

In MetaTrader 5 there are two types of order calculation available:

1. Netting calculation in which there can only be one open position per instrument at any one time:
   • If there is already an open trading position for the instrument, when an additional position is opened in the same direction, the size of the original position increases.
   • Where additional trades are opened for the same instrument but in the opposite direction, either a reduction in the size of the current position takes place, it closes (if the subsequent trade volume is equal to the size of the current open position), or the direction of the trade changes (where the size of the opposite trade is larger than the current open position).
2. Hedging calculation allows for several trading positions (including in several directions) per trading instrument to be open.

If an account is opened with Netting calculation, the trader is not able to have locked positions. Due to this, when a trade for an instrument is opened in the opposite direction, the previous trade closes. If you do not need this type of account, you should select to use hedging in trades when opening an account. This option is only available for accounts which are opened via the MetaTrader 5 platform. It will soon be available in myAlpari.