Stop order not executed by EA

 
My Expert Advisor (EA) is unable to execute all orders.The price hits the stop order and the order disappears without being opened, without any reason in the journal.I only see "cancelled order".What are the possible reasons and how can they be resolved?
 
Frederic Sedonou Ahissin:
My Expert Advisor (EA) is unable to execute all orders.
Just to be clear, your EA sends trade requests while your broker-dealer's trade server executes orders.
Frederic Sedonou Ahissin:
The price hits the stop order and the order disappears without being opened, without any reason in the journal.I only see "cancelled order".

So the stop order is confirmed by your broker-dealer's trade server, and then the order is cancelled by your broker-dealer's trade server upon the stop order's level being struck by price.

Frederic Sedonou Ahissin:
What are the possible reasons and how can they be resolved?

After walking through this precisely, it should be evident that the problem is with your broker-dealer. Contact your broker-dealer to investigate or just switch to another broker-dealer. In the absence of additional info, this kind of broker-dealer conduct tends to remind me of the old bucket shop days of OTC retail trading.