App Fails to Enable in Jira Cloud After Marketplace Installation

I built a Jira Cloud app using Atlassian Connect, and I’m developing locally using ngrok. Everything works fine in dev mode. However, when I install the app from the Marketplace, it is not enabled by default. When I try to enable it from the “Manage Apps” screen, I get the following error: “This app failed to enable. Contact the app vendor for support.”

Here’s what I’ve tried so far:

  1. I installed other apps to check if the issue is specific to my app, and they work fine.
  2. I used the production descriptor file to manually install the app using the Universal Plugin Manager (UPM), but I get the same errors in the console, with the installation loading infinitely

Here are the browser console errors I’ve encountered:

  1. A POST request to the Jira instance returns a 500 error:
POST https://<your-instance><REMOVED-TOKEN> 500

  1. Multiple POST requests to Sentry are blocked by the client

The app used to work fine previously, and I’m not sure what has changed. I’m unable to diagnose the problem and need your help. Thanks in advance!