rag plugin initialize failed

[redhairerINTEL]

backend w/ rag
I already installed requirement

pip install -r ~/intel-extension-for-transformers/intel_extension_for_transformers/neural_chat/pipeline/plugins/retrieval/requirements.txt

But rag plugin still initialize failed.

2024-05-10 04:32:14,308 - intel_extension_for_transformers.neural_chat.utils.error_utils - ERROR - neuralchat error: Generic error
2024-05-10 04:32:14,309 - intel_extension_for_transformers.neural_chat.chatbot - ERROR - build_chatbot: plugin init failed

backend w/o rag
launch successfully

[redhairerINTEL]

degrade protobuf can solve problem.
pip install protobuf==3.20.3

But if i run "pip install -r ~/intel-extension-for-transformers/intel_extension_for_transformers/neural_chat/pipeline/plugins/retrieval/requirements.txt", Protobuf will be back to 5.26 in my environment.