VB.Net Code not executing when value is not nullorempty - asp.net

Question

I'm trying to make fb login for my website. So I put condition if user already exist then it will do login & if not then it perform insert user data.
In following code if string is Not Null Or Empty then I am trying to execute code but by putting breakpoint on my statement I see that if string has value then rest code not executing. What could be the reason? Is I am doing something wrong? My first block of code is working fine(users data fetching from facebook). Problem is in second block where I am checking condition.
Private Sub login_Load(sender As Object, e As EventArgs) Handles Me.Load
FaceBookConnect.API_Key = "XXXXXXX"
FaceBookConnect.API_Secret = "XXXXXXX"
If Not IsPostBack Then
If Request.QueryString("error") = "access_denied" Then
ClientScript.RegisterStartupScript(Me.GetType(), "alert", "alert('User has denied access.')", True)
Return
End If
Dim code As String = Request.QueryString("code")
If Not String.IsNullOrEmpty(code) Then
Dim data As String = FaceBookConnect.Fetch(code, "me")
Dim faceBookUser As FaceBookUser = New JavaScriptSerializer().Deserialize(Of FaceBookUser)(data)
faceBookUser.PictureUrl = String.Format("https://graph.facebook.com/{0}/picture", faceBookUser.Id)
pnlFaceBookUser.Visible = True
lblId.Text = faceBookUser.Id
lblUserName.Text = faceBookUser.UserName
lblName.Text = faceBookUser.Name
lblEmail.Text = faceBookUser.Email
ProfileImage.ImageUrl = faceBookUser.PictureUrl
btnLogin.Enabled = False
End If
End If
If IsPostBack Then
If Not String.IsNullOrEmpty(lblId.Text) Then
Dim query As String = "Select ID, email From users where ID=#id"
con.Open()
Dim cmd As New MySqlCommand(query, con)
cmd.CommandTimeout = 50000
cmd.Parameters.AddWithValue("#id", lblId.Text)
Dim dr As MySqlDataReader = cmd.ExecuteReader()
If dr.HasRows Then
'Do Login Code here
Try
Dim str As String = "select * from users where ID='" + lblId.Text + "';"
Dim cmd2 As New MySqlCommand(str, con)
Dim da As New MySqlDataAdapter(cmd2)
Response.Cookies("User_Type").Value = "users"
Response.Cookies("chkusername").Value = lblId.Text
Response.Redirect(Request.Url.AbsoluteUri)
Response.Write("User Already Exist")
Catch ex As Exception
Response.Write(ex)
End Try
Else
Try
Dim str1 As String = "INSERT INTO users (ID, DP, displayName) values('" + lblId.Text + "', '" + ProfileImage.ImageUrl.ToString + "', '" + lblName.Text + "')"
Dim adapter As New MySqlDataAdapter
Dim command As New MySqlCommand
dr.Close()
command.CommandText = str1
command.Connection = con
adapter.SelectCommand = command
command.ExecuteNonQuery()
Response.Write("User Added")
Catch ex As Exception
Response.Write(ex)
End Try
End If
con.Close()
End If
End If
End Sub
End Class