Need Help with a VB Error Number of indices....

[SpeedwayNative]

I am doing a midterm project and I am having some problems. Here is the assignment:

JM Sales employs 8 salespeople. The sales manager wants an application that allows him to enter a bonus rate. The application should use the rate, along with the 8 salespeople, in an array, to calculate each salesperson's bonus amount. The application should display each salesperson's number (1 through 8) and bonus amount. as well as the total bonus paid, in the interface.

I have the interface correct, my problem is with the section of code below where I am trying calculate the total bonus paid:

Private Sub btnCreate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCreate.Click
        Dim Sales() As Integer = {2400, 1500, 1600, 2790, 1000, 6300, 1300, 2700}
        
        Dim BonusRate As Double
        Dim K As Integer = 0
        Dim Report As String = "Bonus".PadLeft(7) & ControlChars.NewLine
        Dim TotalSales(9) As Integer
        Dim bonus() As Double
        Dim TotalBonus As Double

        Double.TryParse(txtRate.Text, BonusRate)
        Dim ValidBonus As Boolean = BonusRate > 0

        ReDim Preserve bonus(8)

        If ValidBonus Then
            If BonusRate > 0 Then
                Do While K < 8
                    TotalSales(K) = Sales(K, 0) + Sales(K, 1)
                    bonus(K) = (TotalSales(K) * (BonusRate))
                    Report = Report & (K + 1).ToString().PadRight(2) & bonus(K).ToString("n2").PadLeft(5) & ControlChars.NewLine
                    TotalBonus = TotalBonus + bonus(K)
                    K = K + 1
                Loop
            End If
            Report = Report & (K + 1).ToString().PadLeft(1) & ". " & bonus(K).ToString("n2").PadLeft(5) & ControlChars.NewLine
            txtReport.Text = Report
        Else
            MessageBox.Show("Please enter a numerical amount")
        End If

    End Sub

The section below is generating the following 2 Errors:
Number of indices exceeds the number of dimensions of the indexed array
And is pointing out the 2 Red highlighted areas.

If ValidBonus Then
            If BonusRate > 0 Then
                Do While K < 8
                    TotalSales(K) = Sales(K, 0) + Sales(K, 1)                    
bonus(K) = (TotalSales(K) * (BonusRate))
                    Report = Report & (K + 1).ToString().PadRight(2) & bonus(K).ToString("n2").PadLeft(5) & ControlChars.NewLine
                    TotalBonus = TotalBonus + bonus(K)
                    K = K + 1
                Loop
            End If
            Report = Report & (K + 1).ToString().PadLeft(1) & ". " & bonus(K).ToString("n2").PadLeft(5) & ControlChars.NewLine
            txtReport.Text = Report
        Else
            MessageBox.Show("Please enter a numerical amount")
        End If

Any help on this would be greatly appreciated! Thanks