Running Rasa X generates an error: Error happened when trying to save conversation tracker to 'InMemoryTrackerStore'. Falling back to use the 'InMemoryTrackerStore'

I run rasa x. Then, an error is triggered but I don’t know how to overcome it.

rasa.core.tracker_store  - 

Error happened when trying to save conversation tracker to ‘InMemoryTrackerStore’. Falling back to use the ‘InMemoryTrackerStore’. Please investigate the following error: (sqlite3.OperationalError) attempt to write a readonly database

[SQL: INSERT INTO events (sender_id, data) VALUES (?, ?)]

[parameters: ('c4162736def5498d931da6c032d9b578', '{"sender_id": 

“c4162736def5498d931da6c032d9b578”, “event”: “action”, “timestamp”: 1574929654.6607082, “name”: “action_listen”, “policy”: null, “confidence”: null}’)]

(Background on this error at: http://sqlalche.me/e/e3q8).

[2019-11-28 09:27:36 +0100] [5564] [ERROR] 

Exception occurred while handling uri:

http://localhost:5005/conversations/c4162736def5498d931da6c032d9b578 /tracker?include_events=ALL’

Traceback (most recent call last):

  File "c:\app\miniconda2\envs\my_env\lib\site-packages\

sqlalchemy\engine\base.py", line 1244, in _execute_context

    cursor, statement, parameters, context

  File "c:\app\miniconda2\envs\myenv\lib\site-packages\

sqlalchemy\engine\default.py", line 552, in do_execute

    cursor.execute(statement, parameters)

sqlite3.OperationalError: attempt to write a readonly database

ISSUE : the ‘events.db’ is set as ‘read-only’

SOLUTION : unset the ‘read-only’ attribute