Why my animation is stuck on "rendering"?

There can be a few reasons why your animation is stuck on rendering, here are a few things that you can check:

1. Check the size of your animation, large file size tends to have a longer rendering time. If your file is more than 1MB, give it a couple of minutes to wait until the render to complete. 

2. Your animation contains any unsupported features that may cause the render to fail.

Check out this page to see the list of the supported and unsupported features.

3. If none of the above is in your case, then make sure to check if your animation consists of any track matte. There is a known issue with AE 23 track mattes and Lottie as this prevents Lottie from rendering. Disabling track matte works, but if it affects the animation in any manner there's no workaround for AE 23 with it yet.

Projects created with AE 23 (or with AE 23 specific features) aren't backwards compatible with AE 22 and back so using a previous version wouldn't be an option as well. The only option currently would be to make it work without track matte.