I tried to call API in flutterflow but it gave a null response. But inside the postman it gives responce

SOURCE CODE:--

<?php\n// START THE SESSION \nif (session_status() === PHP_SESSION_NONE) {\n    session_start();\n}\n\nrequire 'vendor/autoload.php'; // Include JWT library\n\nuse Firebase\\JWT\\JWT;\ninclude(\"database.php\");\ninclude(\"define.php\");\n\n// Set headers for CORS and content type\nheader(\"Access-Control-Allow-Origin: *\");\nheader(\"Access-Control-Allow-Credentials: true\");\nheader(\"Content-Type: application/json; charset=utf-8\");\nheader(\"Access-Control-Allow-Methods: POST\");\nheader(\"Access-Control-Max-Age: 3600\");\n  header(\"Access-Control-Allow-Headers: Content-Type, Authorization, X-Requested-With,Access-Control-Allow-Origin,Access-Control-Allow-Methods\");\n\n// Initialize the response array\n$response = array();\n\n// Check if the request method is POST\nif ($_SERVER['REQUEST_METHOD'] == 'POST') {\n    // Read incoming JSON data\n    $data = json_decode(file_get_contents(\"php://input\"), true);\n\n    // Check if email and password are provided\n    if (isset($data['email']) && isset($data['password'])) {\n        $email = $data['email'];\n        $password = md5($data['password']);\n\n        // Check if email or password is empty\n        if (empty($email) || empty($password)) {\n            $response = array(\n                \"status\" => 106,\n                \"message\" => \"Email and password fields cannot be empty\"\n            );  \n\n           \n        } else {\n            \n\n            // Query the database for the user\n            $query = \"SELECT * FROM user WHERE `User_Email` = '$email' AND `Password` = '$password'\";\n            $result = mysqli_query($conn, $query);\n            \n            if (!$result) {\n                die(\"Query failed: \" . mysqli_error($conn));\n            }\n            \n            if (mysqli_num_rows($result) == 1) {\n                $row = mysqli_fetch_assoc($result);\n                $json['items'] = $row;\n                $id = $row[\"id\"];\n\n                $Key = bin2hex(random_bytes(32));                \n                $payload = array(\n                    \"id\" => $id,\n                    \"exp\" => time() + 3600 // Token expiration time (1 hour)\n                );\n                $token = JWT::encode($payload, $Key, 'HS256');\n                // Set user ID in session variable\n                $_SESSION['user_id'] = $id;\n\n                $response = array('status' => 200, 'message' => LOGIN_SUCCESS_MSG, 'id' => $id, 'token' => $token);\n\n            } else {\n                $response = array('status' => 201, 'message' => invalid_user);\n            }\n        }\n    } else {\n        $response = array(\n            \"status\" => 203,\n            \"message\" => \"Both email and password fields are required\"\n        );\n    }\n} else {\n    $response = array(\n        \"status\" => 204,\n        \"message\" => Invalid_request_method\n    );\n}\n\n// Encode and output the response as JSON\nprint(json_encode($response));\n?>\n

 It give successfully executed in Postman. but its give a null responce in flutterflow.io

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