How to transfer Session text into Microsoft Access Database

I am using a program from an old class to make an application that takes a user's input from text boxes and drop-down lists, stores the session, and redirects the user to a verification page that shows that the info was saved or NOT saved. I can get the inputs to the redirect page but for the error message states the input was NOT saved, and there no entries into the table
I can't seem to wrap my head around why I can't get this program to store the info into the database. Here is some of the code:
Heres a link to the application with SLN file and other code: 
Application Files



// Code that saves the session information and transfers it to the frmPersonnelVerified.aspx Session["txtInvoice"] = txtInvoice.Text; Session["DropDownList1"] = DropDownList1.Text; Session["DropDownList3"] = DropDownList3.Text; ...