Open AI - Send generic prompt and receive correct answer

I have another project recently done by a freelancer here but I need to help develop/fix the most important feature of the project, which is a OpenAI integration using php/curl. Currently I have prompt/completion feature that I think is working fine TO TUNE THE BOT. So I can set prompt "What is your name" and get correct tuned completion "My name is Bianca your AI assistant". THE ISSUE is that it only words if the user types EXACTELY THE CORRECT prompt - which obviously NEVER happens in a conversation. THE MAIN GOAL OF A IA IS to understand the natural language. Attached I am sending a copy of the TEST CODE. I think the issue is that we need to "send the question to the AI, maybe with all possible answers" AND LET THE AI UNDERSTAND THE QUESTION AND CHOOSE THE ANSWER, or something like that, I dont know, I am not a coder. So, in a nut shell, what I need is someone to complete the test code attached PHP file to send the question to open ai so it can understandt he many different variations like: Do you have a name? or Whats ur name? or What is ur name?