Vertical Lines

Thanks, you help me.

But I have one more problem, if open limit orders and modify limit order, the line mοdify with order.

I want the arrows not modify.

  ObjectCreate("Buy_Signal",OBJ_HLINE,0,TimeCurrent(),Ask);

Of course it doesn't.

1. You're creating a HORIZONTAL line not a vertical one.
   
2. Once it is created, the subsequent ObjectCreate calls fail
3. Always test return codes so you find out WHY

   if (!ObjectCreate(..) Alert("ObjectCreate failed: ", GetLastError());

Either you must use unique names or move the line

int ticket = OrderSend(..)
if (ticket < 0) Alert("OrderSend failed: ", GetLastError());
else Vline("Buy_Signal"+ticket, TimeCurrent(), MediumSpringGreen);

void HLine(string name, double P0, color clr){  //      #define WINDOW_MAIN 0
    if (!Show.Objects)  return;
    /**/ if (ObjectMove( name, 0, Time[0], P0 )){}
    else if(!ObjectCreate( name, OBJ_HLINE, WINDOW_MAIN, Time[0], P0 ))
        Alert("ObjectCreate(",name,",HLINE) failed: ", GetLastError() );
    if (!ObjectSet(name, OBJPROP_COLOR, clr )) // Allow color change
        Alert("ObjectSet(", name, ",Color) [1] failed: ", GetLastError() );
    if (!ObjectSetText(name, PriceToStr(P0), 10))
        Alert("ObjectSetText(",name,") [1] failed: ", GetLastError());
}
void VLine(string name, datetime T0, color clr){    //  #define WINDOW_MAIN 0
    if (!Show.Objects)  return;
    if      (ObjectMove( name, 0, T0, 0 )){}
    else if (!ObjectCreate( name, OBJ_VLINE, WINDOW_MAIN, T0, 0 ))
        Alert("ObjectCreate(",name,",VLINE) failed: ", GetLastError() );
    if (!ObjectSet(name, OBJPROP_COLOR, clr )) // Allow color change
        Alert("ObjectSet(", name, ",Color) [1] failed: ", GetLastError() );
    if (!ObjectSetText(name, TimeToStr(T0, TIME_MINUTES), 10))
        Alert("ObjectSetText(",name,") [4] failed: ", GetLastError());
}