The issue could be due to a few common reasons. An invalid or expired API key will return an error instead of weather data. A misspelled or non-existent city name can also trigger an error message. If you’ve exceeded the API call limits, the response might not include any data. Lastly, it could just be a temporary server issue on OpenWeatherMap’s end. Let me know if this helps resolve the issue or if you’re still running into errors.