How to fix this parameter?

[Michael Wise]

My Code

Private Sub btncalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btncalculate.Click
        Dim oldBalance, charges, credits As Double
        InputData(oldBalance, charges, credits)
        DisplayData(NewBalance(oldBalance, charges, credits), MinPayment(NewBalance(oldBalance, charges, credits)))

    End Sub
    Sub InputData(ByRef oldBalance As Double, ByRef charges As Double, ByRef credits As Double)
        oldBalance = CDbl(txtoldBalance.Text)
        charges = CDbl(txtcharges.Text)
        credits = CDbl(txtcredits.Text)

    End Sub
    Function NewBalance(ByVal oldBalance As Double, ByVal charges As Double, ByVal credits As Double)
        NewBalance = oldBalance + charges - credits + (oldBalance * 0.015)
        

    End Function
    Function MinPayment(ByVal NewBalance As Double, ByVal oldBalance As Double, ByVal charges As Double, ByVal credits As Double) As Double
        If NewBalance <= 20 Then
            Return NewBalance
        Else
            Return 20 + (NewBalance - 20 * 0.1)

        End If

    End Function

    Sub DisplayData(ByVal NewBalance As Double, ByVal MinPayment As Double)
        txtNewBalance.Text = FormatCurrency(NewBalance)
        txtMinPayment.Text = FormatCurrency(MinPayment)


    End Sub

    Private Sub btnexit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnexit.Click
        Me.Close()

    End Sub
End Class

blue lines under this

code-MinPayment(NewBalance(oldBalance, charges, credits)))

error 1- argument not specified for parameter 'charges' Public Function(NewBal ance As Double,oldBalan ce As Double, charges As Double, credits As Double) As Double

error 2-argument not specified for parameter 'credits' Public Function(NewBal ance As Double,oldBalan ce As Double, charges As Double, credits As Double) As Double

error 3-argument not specified for parameter 'oldBalance' Public Function(NewBal ance As Double,oldBalan ce As Double, charges As Double, credits As Double) As Double

[Rodney Roe]

It looks like you havn't filled out your args all the way,
this is what you have;

DisplayData(NewBalance(oldBalance, charges, credits), _ 
MinPayment(NewBalance(oldBalance, charges, credits)))

this is what it should be;

DisplayData(NewBalance(oldBalance, charges, credits), _ 
MinPayment(NewBalance(oldBalance, charges, credits),oldBalance,charges,credits))

notice the extra ,oldBalance,cha rges,credits they fullfill the other minPayment args.

Hope this helps,