Not necessarily. A connection problem and the appliance's local cooking functions are separate observations.
What the observation means
Check the oven's own display and controls before describing it as completely dead. Account access, home Wi-Fi and remote-start permission can affect the app without identifying an oven component fault. Do not assume every connected model allows all programmes to start remotely.
A useful next step
Follow the manufacturer's connection instructions if local operation remains normal. If both local and remote functions fail, record the local message first. Never use a remote command to test an appliance with smoke, overheating, a damaged door or other safety concerns.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.