What's wrong in my VB.NET code?

Dear all,

I'm trying to write the code for a "login" button, to check if the username & password is correct or not and if it's correct check the type, because I have 3 types of users, and each case there should be an update but it's not updating, please check my code below and tell me what's wrong? why it's not updating in the database?

I'm using ASP.NET 2003 and SQL 2000.
Private Sub login_btn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles login_btn.Click
Chec ...