Authentication failed: Token is invalid or has expired.

Hello , I am using
https://github.com/zerodhatech/phpkiteconnect this library but i am getting

Authentication failed: Token is invalid or has expired.

I have modified

$kite = new KiteConnect("pwgqulnx1kxxxxxxx");

$user = $kite->generateSession("request_token_obtained", "rujrjj1wyoictmw999gt0iexxxxxxxx");