Go to Tools > Easy Jira > Issues Admin, then click in the "Settings" button. You will see a few attributes that should be filled in with the information corresponding to your Jira system.
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Jira base URL:
It is the base URL to your Issues system example http://example.atlassian.net
Jira userUser:
It is the user with whom the asset easy Jira will make the request. It is important to clarify that the user must have configured the corresponding roles to perform the administration of Issues.
Jira API token:
You can find more information about how to get it here: https://id.atlassian.com/manage/api-tokens
Jira project keyProject Key:
It is the key of the project to be used. Example DEV.
Results per page:
This attribute defines the number of Issues that the asset should bring in each administrator's page.
How can I get the project key?