4107 "Invalid price" error

 

I have this simple order:

"OrderSend(Symbol(),OP_BUY,Lots,Ask,3,Bid-(StopLoss*Point),0,"BuyOrder",MyNumber,0,Green);"

and I get 4107 error code where the prise has 4 more digits than normal when I'm tsting an expert. Ex: if the price is "1.4275", it takes "1.42753000". Strange thing is that it works perfect for some periods of times and in other periods doesn't. I tested another expert in the same period of time and I've got the same error. As I use "Ask" prise I have no ideea how the price can be ivalid.

Can somebody help?