Azure OpenAI Service expands .NET SDK support

I have upgraded code to 2.0. But it gave some errors. How to fix those errors?

OpenAIClient client = new OpenAIClient(new Uri(openAiEndpoint), new AzureKeyCredential(openAiApiKey));
var chatCompletionsOptions = new ChatCompletionsOptions
{
Messages =

{
new ChatMessage(ChatRole.System, @"You are the virtual assistance of ...."),

new ChatMessage(ChatRole.User, _conversationHistory)

},
Temperature = 0.5f,
MaxTokens = 150,
NucleusSamplingFactor = 0.95f,
FrequencyPenalty = 0,
PresencePenalty = 0,
};

var chatCompletionsResponse = await client.GetChatCompletionsAsync("gpt35turbo", chatCompletionsOptions);
string chatbotResponse = chatCompletionsResponse.Value.Choices[0].Message.Content;