dify - 💡(How to fix) Fix Multi-turn conversation history is being lost

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Dify version

1.14

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

On the left is the conversation history in Dify, where the most recent session appears empty. On the right is the actual status in my application, showing that the AI response was completed successfully. <img width="3099" height="2088" alt="Image" src="https://github.com/user-attachments/assets/39ecbd04-b344-4bb4-b8cc-861592cde54f" />

I am using the API integration method. This issue occurs within my own application, but it does not happen in the native Dify chat interface. I've noticed that when using the API, it seems to only store the initial interaction; all subsequent conversation history is lost, regardless of how many turns occur.

✔️ Expected Behavior

can get all round message in a chat session.

❌ Actual Behavior

All subsequent messages are lost in the history, even though that isn't actually the case. <img width="959" height="578" alt="Image" src="https://github.com/user-attachments/assets/80e3c010-3f86-439c-9385-2cf993b41106" />