Sorting rows value based on if statement using SQL

I made a table where I want to list some data. My goal is to list only 1 row if there are multiple rows with the same value. Let’s say I have 2 rows in MySQL table with the string “asd”. I want to see a single row, even if there are multiple rows with the same value.

<table>
                        <thead>
                            <th>#</th>
                            <th>Expeditor</th>
                            <th>Actiuni</th>                                
                        </thead>
                        <?php
                            $i=1;
                            $id2= $_SESSION["id"];
                            $result= mysqli_query($conn, "SELECT * FROM tb_user WHERE id= $id2");
                            $row = $result->fetch_assoc();
                            $userconn = $row['username'];
                            $rows= mysqli_query($conn, "SELECT * FROM mesajeuseri WHERE username='$userconn'");
                            $num=mysqli_num_rows($rows);
                        ?>
                        <?php if($num == 1){ ?>
                        <?php foreach ($rows as $row): ?>
                        <tr>
                            
                            <td><?php echo $i++; ?></td>
                            <td><?php echo $row["expeditor"] ?></td>

                            <td>
                                <a href="contact2.php?destinatar=<?php echo $row["expeditor"]; ?>">Raspunde</a>
                            </td>
                        </tr>
                            
                        <?php endforeach; ?>    
                        <?php } ?>
            </table>

I tried to use $num as a counter, and if he hit 1 this should stop and print the result. This is how I think it should work. I know this is not secure and stuff, wide open to SQL, this is just an offline project for me to see how things work. With this condition if($num == 1) I get 0 results in my table. If I change it to $num > 0 everything works fine.
This is my table:
table
userconn – represent the current user which is connected to the website and he should only see his messages not all of theme. For example if I’m connected with “dariu” I should see one row with the value “Lordikita” not 7 rows with the same value.