Unless the password has been changed or the token has expired, what could cause the token to be ruin

[Maya assayag]

The Jira app is connected to my third-party app via OAUTH2 
Occasionally, I receive a 403 forbidden error about an invalid access token, but I have not changed my password on Jira and the mechanism for refreshing the access token works most of the time. I would like to know if there is any knowledge of why a new token could be created out of the process and make the token of the user forbidden, such as when the password is changed by the user on Jira. 

[Petter Gonçalves]

Hello @Maya assayag

Thank you for reaching out.

If you are using a default API token, this token never expires and should always work for authentication, unless:

1. You manually revoked the API token
2. You changed your user permissions inside your Atlassian products (Jira, Confluence, etc)

Can you confirm if you are facing one of the scenarios above?