Is there any cookie traffic occurring? My guess is that the server is setting a client-side cookie after the authentication, and you're not mimicking that particular behavior.

You could try deleting the applicable cookie from your browser, and then manually logging into the site. Then, inspect the cookie to see what behavior needs to be implemented.

You might also use Wireshark to do some sniffing to see what traffic is being transmitted.

BTW, you really ought not use HTML tags to format your code. It causes your output to be messed up like it is, and it causes problems for other viewers of your node. The correct way to do it is by using code tags, as in:

<code>
... your code goes here ...
etc.
</code>
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