Hello @GirishReddy
You should use this endpoint: https://developer.atlassian.com/cloud/jira/platform/rest/v3/api-group-users/#api-rest-api-3-user-email-get
Returns a user’s email address regardless of the user’s profile visibility settings. For Connect apps, this API is only available to apps approved by Atlassian, according to these guidelines. For Forge apps, this API only supports access via asApp() requests.
Don’t forget to add new OAuth 2.0 scope read:email-address:jira in the manifest.
Hope that help !