不调用Php类方法

I have a problem with my PHP class, when the user wants to follow another user the follow method is called and when the user wants to stop following the delete_follow is called:

class Follow {

    protected static $table_name = "interests";


    public function follow() {
        global $dbh;
        $sql = "INSERT INTO ".self::$table_name." (company_id,user_id,likedate) VALUES (:company_id,:user_id,NOW())";
        $follow = $dbh->prepare($sql);
        $follow->bindParam(':user_id',$_SESSION['user_id']);
        $follow->bindParam(':company_id',$_GET['company']);
        if($follow->execute() == true){
            header("Location: profile.php?company=".$_GET['company']."");
            exit;
        } else {
            header("Location: error.php");
            exit;
        }
    }

    public function delete_follow() {
        global $dbh;
        $sql = "DELETE FROM ".self::$table_name." WHERE company_id = :company_id AND user_id = :user_id LIMIT 1";
        $delete_follow = $dbh->prepare($sql);
        $delete_follow->bindParam(':user_id',$_SESSION['user_id']);
        $delete_follow->bindParam(':company_id',$_GET['company']);
        if($delete_follow->execute() == true) {
            header("Location: profile.php?company=".$_GET['company']."");
            exit;
        } else {
            header("Location: error.php");
            exit;
        }
    }   


}

My problem is that when the delete_follow method is called it actually calls the follow method I have no idea what is going on.

Here is the code for the follow buttons:

if(isset($_POST['follow'])) {
    $follows = new Follow();
    $follows->follow();
}

if(isset($_POST['delete_follow'])) {
    $follows = new Follow();
    $follows->delete_follow();
}

Help please.

I would imagine that there is an error in your form. Perhaps it would be better to have one field follow with a boolean value, say yes or no.

The name of your class is Follow. The first method in your class is called follow(). PHP is case insensitive in this aspect and treats that follow() method as the constructor. So this statement--$follows = new Follow()--actually calls the follow() method from your class. Therein could lie your problem.