I use Playground Chatbots for conversation. But, i lose them even if i access anything else or go other chatbots in Playground. How can i access my recent chats?
You cannot.
The playground is a simple developer sandbox, not a consumer product.
You can. A history is maintained by the playground when using chat, or alternately, threads can be viewed which were used by assistants.
At the upper-right, a clock icon:
Receive a 30-day history of every submission:
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