Issue Summary

The Opsgenie Salesforce Service Cloud integration does not work with Salesforce Sandbox instances.

We should mention this within the instructions on the integration in-app as well, please provide the text for it.
https://support.atlassian.com/opsgenie/docs/integrate-opsgenie-with-salesforce-service-cloud/

Workaround

The only workaround available at the moment is to use the Production Salesforce instance to test the integration with Opsgenie.