@pete1 Glad, you got a workaround with Axios, I will find time to try your suggested method out.
For now, I also got a workaround am using already with a code wrapper package as posted in this thread https://community.openai.com/t/gpt-completion-chatgpt-chatml-format/81882
The JS version is working for me with the Expressjs configuration without axios.
If you want to see it in action you can check the repo out
https://github.com/AiHiPUniversity/ai-chatbot-openai-sveltekit-boilerplate-1/blob/main/server/server.js
Hopefully, Openai will update their NPM package soon to make this more straightforward to implement like GPT-3 API.