Same issue here, toggled ai chats only and selected one of the default questions, maybe api met hn hug of death(?)
1. When a query is sent while another query is being processed, it consistently triggers a 400 bad request error. Subsequent queries also yield the same error code.
2. Although less common, random queries can sometimes result in a Bad Request error. I do not know how helpful this information is, but I can provide the chat_id associated with the instance: 677cfad3-5084-40d0-81d0-08592b5927f5.