registration কোডটা কাজ করছে না , সমাধান চাই

<div id="register" class="animate form">
                            <form  action="registration.php" method="POST" enctype="multipart/form-data"> 
                                <h1> Sign up </h1> 
                                <p> 
                                    <label class="uname" data-icon="u">Your name</label>
                                    <input id="usernamesignup" name="name" required="required" type="text" placeholder="myname" />
                                </p>
                                <p> 
                                    <label class="youmail" data-icon="e" > Your email</label>
                                    <input id="emailsignup" name="email" required="required" type="email" placeholder="mysupermail@mail.com"/> 
                                </p>

                                <p> 
                                    <label class="youpasswd" data-icon="p">Your Phone</label>
                                    <input type="text" name="phone" required="required" type="text" placeholder="0132342441"/>
                                </p>
                                
                                <p> 
                                    <label class="youpasswd" data-icon="p">Your session</label>
                                    <input name="session" required="required" type="text" placeholder="11-12"/>
                                </p>
                                
                                <p> 
                                    <label class="youpasswd" data-icon="p">Your Batch NO.</label>
                                    <input name="batch" required="required" type="text" placeholder="batch"/>
                                </p>
                                
                                <p> 
                                    <label class="youpasswd" data-icon="p">Your designation</label>
                                    <input name="designation" required="required" type="text" placeholder="position"/>
                                </p>
                                
                                <p> 
                                    <label class="youpasswd" data-icon="p">Your present address</label>
                                    <input name="address" required="required" type="text" placeholder="address"/>
                                </p>

                                <p> 
                                    <label class="youpasswd" data-icon="p">Your Terminal Degree</label>
                                    <input name="degree" required="required" type="text" placeholder="degree"/>
                                </p>

                                <p> 
                                    <label class="youpasswd" data-icon="p">Your photo</label>
                                    <input type="file" name="photo">
                                </p>

                                <p class="signin button"> 
                                    <input type="submit" value="submit"/> 
                                </p>

                                <p class="change_link">  
                                    Already a member ?
                                    <a href="#tologin" class="to_register"> Go and log in </a>
                                </p>
                            </form>
                        </div>

<?php require_once('connection.php')?>

<?php
    
    if (isset($_POST['submit'])) {
        
        $name=$_POST['name'];
        $email=$_POST['email'];
        $phone=$_POST['phone'];
        $session=$_POST['session'];
        $batch=$_POST['batch'];
        $designation=$_POST['designation'];
        $address=$_POST['address'];
        $degree=$_POST['degree'];
        $photo=$_FILES['photo']['name'];
        $photo_tmp_name = $_FILES['photo']['tmp_name'];

    move_uploaded_file($photo_tmp_name, "photo/$photo");

    mysql_query("insert into member(name,email,phone,session,batch,designation,address,degree,photo) values('$name','$email','$phone','$session','$batch','$designation','$address','$degree','$photo')");

    echo "Data successfully inserted";
    }

else{
    echo "not inserted";
}


?>