C# Error: value of type 'int' cannot be used as a default parameter because there are no standard conversions

Dear Sir,

I have an error "  A value of type 'int' cannot be used as a default parameter because there are no standard conversions to type 'KtToast.Hosts'" and "A value of type 'int' cannot be used as a default parameter because there are no standard conversions to type 'KtToast.Positions'"

Please Guide me

public sealed class KtToast : Component
{
    'Below line code error	
    public KtToast.SnackbarResult Show(Form owner, string message, KtToast.MessageTypes type = 0, int duration = 3000, string action = "", KtToast.Positions position = 1, KtToast.Hosts host = 2)
    {
    } 
    public enum Hosts
    {
        Screen,
        Control,
        FormOwner
    }

    public enum Positions
    {
        TopLeft,
        TopCenter,
        TopRight,
        MiddleLeft,
        MiddleCenter,
        MiddleRight,
        BottomLeft,
        BottomCenter,
        BottomRight,
        Custom
    }

    public enum SnackbarResult
    {
        AutoClosed,
        UserClosed,
        ActionClicked
    }
}