[Bug] [Application] The user has connected to the openAI model and has conversations through the interface. The role role is user and can be adjusted normally. In a simple application, after changing the "system user" to "user", the Q&A is normal. However, in advanced orchestration, the "system user" will be changed to "user" and the big model will not be called normally.

[Bug] [Application] The user has connected to the openAI model and has conversations through the interface. The role role is user and can be adjusted normally. In a simple application, after changing the "system user" to "user", the Q&A is normal. However, in advanced orchestration, the "system user" will be changed to "user" and the big model will not be called normally. #4900