response.redirect

Hi, I have 2 factors authentication. So when the user logged in the first time, they are redirected to the 2nd authentication page, which generate codes at Page_Load to send out a token through SMS.


However, if the user clicks other link. It will redirect back to the 2nd authentication page. however, because my codes are inside Page_Load, it will re load again.. Any idea how do I go about doing this? I used a session to check, but I dont think it's a good idea.. 


Thanks! 
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