Problem updating Gridview using a pop up - VB.NET

[jespina]

Please help me update a gridview using a pop up.
It couldn't get the primary key of the selected row.
these are my codes:

Protected Sub btnSaveRemarks_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSaveRemarks.Click

strSQL = "UPDATE CandidateScreening SET Remarks = @Remarks, Status = @Status WHERE ID ='" & lblID.Text & "'"

conn = New SqlConnection(ConfigurationManager.AppSettings("RRMS").ToString())

conn.Open()

With cmd

.Parameters.Clear()

.Parameters.AddWithValue("@Remarks", txtInitialInterviewRemarks.Text)

.Parameters.AddWithValue("@Status", ddlPassOrFail.SelectedItem.Value)

'.Parameters.AddWithValue("@SupportedDoc", txtMI.Text)

.Connection = conn

.CommandType = CommandType.Text

.CommandText = strSQL

Try

.ExecuteNonQuery()

Catch ex As Exception

Response.Write("Error: " & ex.Message)

End Try

End With

conn.Close()

updateInitial()

gvwInitInterview.DataBind()

ASPxPopupControl1.ShowOnPageLoad = False

End Sub

--------------

Protected Sub gvwInitInterview_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles gvwInitInterview.RowCommand

If e.CommandName = "Edit" Then
ASPxPopupControl1.ShowOnPageLoad = True

Dim row As GridViewRow = CType(CType(e.CommandSource, Control).NamingContainer, GridViewRow)
lblID.Text = gvwInitInterview.DataKeys(row.RowIndex).Value

End If
End Sub

---- Thank you.