DESCRIPTION: below you can understand why your trades closed by itself
POSIBBLE REASON: With stop out, if your margin level drops below the stop-out level, your positions may be closed automatically in order to protect you from further losses.
RESOLUTION STEP:
- When your order reached the stop out level where it is unable to sustain an open position, your pending orders will be canceled and your open positions will be forcibly be closed (also known as "forced liquidation").
- Kindly make sure that you have enough funds in the future to cover all your open positions in order to prevent stop-out to happens to your open positions
For further check refer to https://community.deriv.com/t/stop-out-in-deriv-mt5/28609 or https://deriv.com/tnc/trading-terms.pdf (under section 3.2. Stop out level)