Can someone help me with OrderClose error 4051

 
 

https://docs.mql4.com/runtime/errors

So you have an invalid parameter in the OrderClose function. Take the function and check that the parameters you are supplying are sensible (correct type etc)

https://docs.mql4.com/trading/orderclose

 
ronwhite:
No mind readers here, no code, no help.
 
Using the Dark Side of the force I have determined that you have done something silly like put "Ask" in quotation marks within the function call (so the type is string rather than double.)
Reason: