No improvised supply should be used as a diagnostic workaround. Cooking appliances can have substantial power requirements and model-specific connection arrangements.
What the observation means
A plug-looking connection does not establish that an ordinary extension is suitable. Moving the appliance to reach another socket can also strain concealed connections and mounting points. This is an electrical assessment task rather than a normal owner check.
A useful next step
Keep the oven unused if its supply is in doubt and report what stopped working. Do not alter plugs, adapters or protective-device ratings to make it run. A competent person should distinguish the installation problem from any appliance fault.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.