Can't create GitHub branch

[박예랑]

I wanted to create GitHub branch. But I couldn't.

First, I couldn't find my repository. So I click "Configure GitHub integration" Button.

But page wasn't loaded. And error message card was popped up. And the meaning of the message is as follows.

There was a problem on our end

If this issue persists, please share this information with your administrator so they can contact support.

reload page

(It's Korean.)

When I entered App category, "GitHub for Jira" App is already installed.

What should I do for this error..?

(Upper page's url was  https://{project}.atlassian.net/plugins/servlet/ac/com.github.integration.production/github-post-install-page)