Hi @SunilDe!
Referencing our Troubleshooting Resource Connections guide,
"If your OAuth2 resources are prompting you to re-authenticate on a regular basis, then there is likely an issue with the refresh token/flow. Make sure the refresh token is being saved properly after authenticating (you can check the token status in the resource), and that you have the required scopes to refresh the access token. You may need to manually create the re-authentication flow in a custom auth if it is non-standard."
Would you mind sharing a screenshot of your current resource setup page? Feel free to block out any secrets!