Inserting Data When User Logon

I am inserting data into Access when user logs on:
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SQL = "INSERT INTO tblLog (fldUserName,fldTimeIn,fldSID) VALUES ('" & u & "',#" & session("Date") & "#,'" & session.SessionID & "')"
con.Execute(SQL)
.....................
in here it inserts the date :01/09/2003

But when logging out :
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SQL="UPDATE tblLog SET fldOffline=1,fldProper=1 WHERE fldUserName= '" & session("admin") & "' AND fldTimeIn=#" & session("date") & "# AND fldOffline=0"
con.execute(SQL)
...............
it doesn't update the record.If I eliminate the date query here,it updates there is no syntax error is there?