GitHub history not showing on Jira ticket page

Question

We're using the Cloud version of Jira. It's connected to GitHub (confirmed via Development Tools page) but when we view a ticket the Development app briefly appears and then disappears. It was working fine before the holiday break, but now we can't see pull requests. The DVCS accounts page shows Smart Commits are selected for all our repositories.
I don't see any errors, so I'm not sure where to start with investigating this.

Paul Henman · Answer

I've opened a support ticket - https://getsupport.atlassian.com/servicedesk/customer/portal/23/JST-355966

Paul Henman · Answer

I changed the OAuth credentials to use my GitHub account but the problem persists. :(

Paul Henman · Answer

Looks like our OAuth setting is via a user who no longer has access to our GitHub organisation.