If i understand the API correctly, there is no automatic thread management. So this line will always create a new thread every single time it’s called.
// Create a new thread for each conversation
const threadResponse = await openai.beta.threads.create();
so each time you call askGPT, a new thread is created.
There does not seem to be any method/API for getting a list of created Threads, which means that you need to store the thread id on your side to a database.
So instead of always calling create(), you need to check if a thread id exists in your database, then fetch it with openai.beta.threads.retrieve(thread_id). And if it doesn’t exist, then create a new thread.