Uncaught InputException (400) 'Invalid `api_key` or `access_token`

I'm trying to get quotes for some tickers but the error says access_token is invalid. The API verison is 3.0.2b. Here's what I'm doing.

Login file

if(isset($_GET['request_token'])){
	try {
		$user = $kite->generateSession($_GET['request_token'], KITE_SECRET);

		echo "Authentication successful. \n";
		$kite->setAccessToken($user->access_token);

		$connect = mysqli_connect($host, $username, $password, 'zerodha');
		$saveAccessTokenQ = "UPDATE zerodha_config SET _value = '".$user->access_token."' WHERE _key = 'access_token'; UPDATE zerodha_config SET _value = '".mysqli_real_escape_string($connect, $_GET['request_token'])."' WHERE _key = 'request_token';";
		;
		$saveAccessToken = mysqli_multi_query($connect, $saveAccessTokenQ); //save access token to DB

	} catch(Exception $e) {
		echo "Authentication failed: ".$e->getMessage();
		throw $e;
	}
} else {
	header('location: https://kite.trade/connect/login?v=3&api_key='.KITE_API);
	exit();
}

Get quote file

$connect = mysqli_connect($host, $username, $password, 'zerodha');
$loadConfig = mysqli_query($connect, "SELECT _key, _value FROM zerodha_config");
while ($row = mysqli_fetch_assoc($loadConfig)) {
  $config[$row['_key']] = $row['_value']; //access token loaded from DB
}

$kite = new KiteConnect(KITE_API);
$kite->setAccessToken = $config['access_token'];

try {
	$quotes = $kite->getQuote($config['tickers']); //Error on this line
	var_dump($quotes);
} catch(Exception $e) {
	throw $e;
	// requestLogin();
}

So first I visit the login page and login to Kite. This generates an access token and saves it in DB. Then I navigate to the second file and the error comes up:
Fatal error: Uncaught InputException (400) 'Invalid `api_key` or `access_token`.' thrown in /home/webserver/public_html/zerodha/phpkiteconnect-kite3/kiteconnect.php on line 899

What am I doing wrong?