Missing permission after installation

We have been experiencing a permission issue with our Forge app. The app is making Confluence API requests in an install trigger (i.e., directly after app installation). In some seemingly random cases, the app doesn’t have the necessary permission when the install trigger is executed and the API returns the following error:

  "message": "Current user not permitted to use Confluence",
  "statusCode": 403

Although it makes the install trigger unreliable (and unsuitable for some use cases), this hasn’t been a problem for us so far because we are not running critical code in the trigger. Usually, the app gains access shortly after, so users don’t notice it.

However, we recently had a case where other Forge functions in our app were still unable to access the API a few hours after the installation. As a result, our customer couldn’t use the app and uninstalled it. Luckily, they were patient enough to reinstall it again after we contacted them. After the reinstallation, it took more than two hours until the app had permission to access the API.

Has anyone else encountered this problem? I have reported it a while ago, but it didn’t receive much attention. This issue is pretty critcal because it results in a terrible user experience and there’s nothing that we or our customers can do about it.