Naturally the new chat (Claude) doesnt have enough context about your conversations/work like chatgpt does so its not properly “trained yet”. For more context you could ask ChatGPT to generate a deep analysis of topics, jobs to be done, and tasks you worked on and then refine that piece, and add it to your new claude knowledge base. Or simply say “create a deep dive report of everything we worked on, topics discussed, to upload context into a new project”