var factory = new ConnectionFactory(){ HostName = _rabbitMQ_Hostname, UserName = _rabbitMQ_Username, Password = _rabbitMQ_Password};

using (var connection = factory.CreateConnection())
using (var channel = connection.CreateModel())
{
    channel.QueueDeclare(queue: _autoCancellationPNS_QueueName,
    durable: true,
    exclusive: false,
    autoDelete: false,
    arguments: null);

    string message = appointmentId.ToString();
    var body = Encoding.UTF8.GetBytes(message);
    IBasicProperties properties = channel.CreateBasicProperties();
    properties.DeliveryMode = 2;
    channel.BasicPublish(exchange: _rabbitMQ_Exchange,
        routingKey: _autoCancellationPNS_RoutingKey,
        basicProperties: properties,
        body: body);
    returnMessage.ShortMessage = "Added to queue";
    returnMessage.LongMessage = "Added to queue";
    logger.Debug("|Added to queue");
}