Describe the bug
I have a Premium Service Bus namespace with a topic configured to receive messages up to 100MB.
I have created a basic .NET 5 console app using the latest 7.2.1 Azure.Messaging.ServiceBus package.
I send to the topic a message with a string slightly over 1MB which was the old limit.
The message is sent without error.
In the queue the message exists but it is empty and with a size of 0. (checked with the azure portal service bus explorer, and queue explorer application).
I have tested both ServiceBusTransportType.AmqpWebSockets/AmqpTcp TransportTypes

Expected behavior
The message should not be empty.

Actual behavior (include Exception or Stack Trace)
The message with a content over 1MB is sent successfully but appears to have an empty content in the queue.

To Reproduce

string fileContent = File.ReadAllText("file.Log");

        var option = new ServiceBusClientOptions();

        option.TransportType = ServiceBusTransportType.AmqpTcp;

        client = new ServiceBusClient(connectionString, option);

        sender = client.CreateSender(queueName);

        await sender.SendMessageAsync(new ServiceBusMessage(fileContent));

Environment:

• Azure.Messaging.ServiceBus 7.2.1
• Windows 10 .NET 5
• VS 16.11.3