Hi! I see you're encountering the "Try again later" error when trying to access the Sling app on your iPhone with iOS 18.7. I'd be happy to help you get this sorted out. Just to better assist you, have you noticed if this happens immediately upon opening the app, or does it occur after some navigation or login attempt? Also, have you tried any fixes so far like restarting the app or your phone?

Meanwhile, here are some straightforward steps to try that often resolve such issues:

1. Check Your Internet Connection:
Make sure your iPhone has a stable internet connection, either Wi-Fi or cellular data. You could try toggling Wi-Fi off and on or switching to cellular to rule out connectivity issues.

2. Force Close and Reopen the Sling App:
Double tap the home or swipe up (depending on your iPhone model) to see recent apps, then swipe the Sling app away to close it. Open it again to see if the error clears.

3. Restart Your iPhone:
Power off your iPhone completely, wait about 30 seconds, and then turn it back on. This often clears minor glitches.

4. Update the Sling App:
Go to the App Store, search for Sling, and check if there's an update available. Running the latest version helps because older versions might have bugs or server compatibility issues.

5. Reinstall the Sling App:
If the issue persists, delete the Sling app from your device and reinstall it fresh from the App Store. This clears app cache and corrupted files that might cause errors.

6. Verify Your Location:
Sling TV restricts streaming in certain regions. If you are traveling or using a VPN, that could cause this message. Try disabling any VPNs and ensure you're in a supported region.

7. Check for System Updates:
Since you are on iOS 18.7, make sure your iPhone software is up to date (Settings > General > Software Update). Sometimes app compatibility depends on the latest OS patches.

If after trying these steps the error still appears, there might be a temporary server-side issue with Sling, or something specific with your account. In that case, I can help you escalate the issue or guide you to Sling support for account verification.

Could you please try these and let me know which step you get to or if any changes appear? That way, I can guide you more precisely!