AI Chat not returning responses – other Assistant modules working

Which version of assistant are you using?

2.12.0

Which version of Nextcloud are you using?

32.0.5

Which browser are you using? In case you are using the phone App, specify the Android or iOS version and device please.

Brave, Firefox, Chrome

Describe the Bug

Hi,
I am running:

• Nextcloud AIO: 12.5.1
• Nextcloud: 32.0.5
• Nextcloud Assistant: 2.12.0
• OpenAI API (paid plan, working and verified)

I am experiencing an issue specifically with the AI Chat module inside Nextcloud Assistant.

When I enter a question in AI Chat, the UI shows that it is processing (“working” state), but no response is ever returned. The conversation remains stuck indefinitely.

However:

• ✅ Text Processing works
• ✅ Translation works
• ✅ Emoticon generation works
• ✅ Image generation works
• ✅ Assistant Talk Bot works

So the OpenAI API key is valid and functional, and requests to the provider are clearly succeeding in other Assistant modules.

A few versions ago everything was working correctly. The issue appeared only recently.

What I have already tried:

• Recreated all AIO containers
• Switched between different OpenAI models (including gpt-4o-mini)
• Tested in multiple browsers (Chrome + Firefox + Brave)
• Reverse proxy (Nginx Proxy Manager) configuration is unchanged and confirmed working

Only the AI Chat module fails to return a response.

Given that other modules work and only Chat fails, this seems to be specific to the chat endpoint or streaming handler introduced in Assistant 2.12.0.

Has anyone encountered this behavior, or is this a known regression?

Expected Behavior

All is written above.

To Reproduce

All is written above.

Reproduce the AI Chat failure with Assistant 2.12.0 and compare it with the working Assistant modules, then inspect the chat endpoint or streaming handler mentioned in the report. Done means a question no longer remains stuck and a response is returned in the chat UI.