My app show error "Rate limit exceeded"


I used the below code for connecting twitter account into my website:

 $twitteroauth = new TwitterOAuth(CONSUMER_KEY, CONSUMER_SECRET, $_SESSION['TWITTER_token'], $_SESSION['TWITTER_token_secret']);
    $user_info = $twitteroauth->get('account/verify_credentials');
    $user_info_tw = json_decode( json_encode($user_info), true);  
    echo "<pre>";print_r($user_info_tw);echo "</pre>";
        if(!empty($user_info_tw['errors'])){    echo "<br><br><br>";
            foreach($user_info_tw['errors'] AS $error){
                echo    $error['message'];
            echo $_SESSION['user_info_tw']=$user_info_tw['id'];
            echo $_SESSION['user_screen_name_tw']=$user_info_tw['screen_name'];   


it was working fine but from Friday onward my app show error

“Rate limit exceeded”

Whereas i didn’t used my app( not log in or post) but it shows error continuously .How can i solve this.?
Please help me because i am going to live my app.