Gemini API key does not Validate

When a Gemini key is entered, validation emits the error: ✗ Gemini connection failed: Gemini API operation failed: operation=models/gemini-2.5-flash:generateContent, status_code=403, response={ “error”: { “code”: 403, “message”: “Method doesn’t allow unregistered callers (callers without established identity). Please use API Key or other form of API consumer identity to call this API.”, “status”: “PERMISSION_DENIED” } }