update

Author: mrbullwinkle

articles/ai-services/openai/includes/chat-completion.md

@@ -547,7 +547,7 @@ The token counting portion of the code demonstrated previously is a simplified v
 
 ## Troubleshooting
 
-### Do not use ChatML syntax with the Chat Completions endpoints
+### Do not use ChatML syntax with the Chat Completions endpoint
 
 We have found that some customers will try using the [legacy ChatML syntax](./chat-markup-language.md) with the chat completion endpoints and newer models. ChatML was a preview capability that only worked with the legacy completions endpoint with the `gpt-35-turbo` version 0301 model which is [slated for retirement](../concepts/model-retirements.md). Attempting to use ChatML syntax with newer models and the chat completions endpoint can result in unexpected model response behavior and is not recommended.