Need help with API vision in C# (Error 500)

API
1

I am using the OpenAI API to create descriptions from images, but currently struggling with the requests. I always get a 500 errors. I am using C# with the official library version 2.0.0. The code is below. If anyone knows what is wrong, please help.

async Task TestGPT()
{
    //Convert image to byte array
    var imageJpg = "C:\\Users\\<myPath>";
    byte[] image = File.ReadAllBytes(imageJpg);

    List<ChatMessage> messages = new List<ChatMessage>() 
    {
        new SystemChatMessage("Describe, briefly, the image."),
        new UserChatMessage(ChatMessageContentPart.CreateTextPart("Hello, what can you see on the image"), ChatMessageContentPart.CreateImagePart(new BinaryData(image),"image/jpeg", ChatImageDetailLevel.Low))
    };

    ChatCompletion res = await _client.GetChatClient("gpt-4o-mini").CompleteChatAsync(messages , null);

    Console.WriteLine($"Asystent: {res.Content[0].Text}");

    Console.ReadKey();
}

The error appears on code line:

    ChatCompletion res = await _client.GetChatClient("gpt-4o-mini").CompleteChatAsync(messages , null);

Error:

The server had an error processing your request. Sorry about that! You can retry your request, or contact us through our help center at help.openai.com if you keep seeing this error

Any suggestion?