Open a new order !!

 
When I do a back test using MetaTrader 4 tester , I notice that the tester doesn't open buy order unless the sell order is closed , and doesn't open sell order unless the buy order is closed.
I'm asking if there a way to let the tester open a new order even if the previous order is not closed.
Thank you.
 
Ammar,

are you sure the mql code is correct? If possible, post it here.

Regards.