Custom domains are not supported on Free plans. Therefore, if your app was previously on a paid plan and is now on a Free plan, the connection to your custom domain will no longer work.
That's why you might be seeing the message: “This used to be a Bubble app! The domain yourdomain.com is connected to a Bubble application, but the application’s plan does not offer a custom domain.”
If you’d like your site to be accessible again, you have two options:
1. Use the Bubble subdomain (ending in .bubbleapps.io) which is always available on the Free plan. If you'd like to revert your app back to its default Bubble subdomain (like yourapp.bubbleapps.io) and remove the custom domain setup, here’s how you can do that:
Open your app in the Bubble editor.
Head to the Settings tab, then click on Domain/Email.
There, click “Delete this domain name” to disconnect your custom domain.
Once that’s done, your app will automatically use the default Bubble subdomain again. If the app doesn’t show up right away, try clearing your browser cache, since custom domain redirects can get cached locally.
2. Re-upgrade the app to at least the Starter plan. Here's how:
Open your app’s Editor.
Go to the Settings tab.
Open the Plan section.
Click Reactivate plan (or Change Plan), then select the Starter plan and confirm.
Note: You may be asked to re-enter valid billing details if needed.
Once reactivated, your plan will be billed at the current rate, and all features (including custom domains) will be restored.