Hi there! I’m sorry to hear your NHL app has stopped working on your Mac. Let’s get it sorted out together.

First, can you tell me a bit more about what’s happening? For example:
- Is the app crashing, freezing, or just not opening at all?
- Have you seen any error messages?
- Did the issue start recently after an update or some change?

Meanwhile, here are some general steps to try, especially on your Mac running OS X 10.15.7:

1. Restart the App: Quit the NHL app completely (use Cmd + Q to ensure it’s closed), then open it again.

2. Restart Your Mac: Sometimes a fresh start clears out temporary glitches.

3. Check for App Updates: Open the App Store and see if there’s an update available for the NHL app. The latest version may fix bugs.

4. Clear Cache or Data: Though macOS apps don’t have a direct “clear cache” button, you can try deleting the app’s cache files. Here’s how:
- In Finder, press Cmd+Shift+G and type ~/Library/Caches/
- Find any folders related to NHL or the app’s developer and move them to Trash.
- Restart the app.

5. Check your internet connection: Make sure your network is stable. Occasionally issues with streaming apps stem from poor connectivity.

6. Reinstall the App: Delete the NHL app from your Applications folder, then reinstall it from the Mac App Store.

If the app still doesn’t work properly, could you tell me if you’re trying to stream games or just browse scores and news? Also, what version of the app you have (if you see that), and whether you usually use safari or some other browser alongside the app?

Once I get a bit more info, I can help you dig deeper or suggest other fixes. Looking forward to your reply!