VB.NET SQL Server: Must declare scalar variable

I am trying to make a query that deletes the user from my database. But when i confirm to delete the user it gives me an error:

System.Data.SqlClient.SqlException (0x80131904): Must declare the scalar variable "@Username".

Imports System.Data.SqlClient
Public Class DeleteForm
Private Sub btnDelete_Click(sender As Object, e As EventArgs) Handles btnDelete.Click
    Dim RetVal As Integer
    Dim conn = New SqlConnection("Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=dbProject;Integrated Security=True")
    Using cmd = New SqlCommand("select count(*) from tblLogin where username = @Username and password = @Password", conn)
        cmd.Parameters.Add("@Username", SqlDbType.VarChar).Value = txtUsername.Text
        cmd.Parameters.Add("@Password", SqlDbType.VarChar).Value = txtPassword.Text

        conn.Open()
        If conn.State = ConnectionState.Open Then
            RetVal = CInt(cmd.ExecuteScalar)
            If RetVal = 1 Then
                If txtPassword.Text And txtCheckPassword.Text <> "" Then
                    If txtCheckPassword.Text = txtPassword.Text Then
                        Dim cancConf As Integer = MessageBox.Show("This cant be undone!" & vbCrLf & "Are you sure?", "Warning!", MessageBoxButtons.YesNo, MessageBoxIcon.Warning)
                        If cancConf = DialogResult.Yes Then
                            Try
                                Dim queryDelete As String = "DELETE FROM tblLogin WHERE username = @Username"
                                Dim cmdDelete As New SqlClient.SqlCommand(queryCancellazione, conn)

                                cmdCancellazione.ExecuteNonQuery()
                                MsgBox("Account deleted succesfully!")
                                cmdCancellazione.Dispose()
                                conn.Close()

                                LoginForm.Show()
                                Me.Close()
                            Catch ex As Exception
                                MsgBox(ex.ToString())
                            End Try
                        ElseIf cancConf = DialogResult.No Then

                        End If
                    Else
                        MsgBox("The passwords arent matching!", MsgBoxStyle.Exclamation)
                    End If
                ElseIf txtPUtenteCANC.Text <> "" And txtPUtenteCONF.Text = "" Then
                    MsgBox("Please, confirm the password")
                End If
            Else
                MsgBox("User not found!", MsgBoxStyle.Exclamation)
                txtNUtenteCANC.Clear()
                txtPUtenteCANC.Clear()
                txtPUtenteCONF.Clear()
                txtNUtenteCANC.Select()
            End If
        Else
            MessageBox.Show("The connection is not open!" & vbCrLf & "The program will close", "Warning!", MessageBoxButtons.OK, MessageBoxIcon.Error)
            End
        End If
    End Using
End Sub
End Class

You have added that parameter to the SELECT COUNT command but not to the DELETE command.

Dim queryCancellazione As String = "DELETE FROM tblLogin WHERE username = @Username"
Dim cmdCancellazione As New SqlClient.SqlCommand(queryCancellazione, conn)
cmdCancellazione.Parameters.Add("@Username", SqlDbType.VarChar).Value = txtUsername.Text