Can not use custom tracker store: "Custom tracker store not found. Using InMemoryTrackerStore instead"

I am having problems using the custom tracker store. Even I set my rasa project directory to PYTHONPATH but I still get this warning:

Tracker store with type 'tracker.CustomMongoTrackerStore' not found. Using `InMemoryTrackerStore` instead.

Here’s endpoints.yaml

  # type: mongod
  type: tracker.CustomMongoTrackerStore
  url: ...
  db: Conversation

Is there any way to solve this problem?

Could anybody please help?

Rasa version: 2.3.2

Python version: 3.7.5

Can someone help me? please

Hi, please do you have any information about this error? Can you fix this error?