member names cannot be the same as their enclosing type C#

Method names which are same as the class name are called constructors. Constructors do not have a return type. So correct as:

private Flow()
{
   X = x;
   Y = y;
}

Or rename the function as:

private void DoFlow()
{
   X = x;
   Y = y;
}

Though the whole code does not make any sense to me.