You mentioned you "renewed the key multiple times". When you "regenerate" the key, the old key would expire (after certain amount of grace period). The old key is still in your GoogleService-Info.plist and Firebase ML Kit Cloud Image Labeling uses the old key from GoogleService-Info.plist. That's why you saw the error message.

For other developers: In general, check your API_KEY in GoogleService-Info.plist exist in Google Cloud Platform developer console.

See screenshot: enter image description here

And if it doesn't exist, please re-download / replace your GoogleService-Info.plist from Firebase Developer Console.

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