The appliance is designed for a specified ambient range, and its control arrangement can make cold surroundings affect the compartments unexpectedly. A cold room does not guarantee correct frozen storage.
What the observation tells you
Some designs respond to conditions sensed in one part of the system. The precise mechanism and permitted range must come from the model information, not a generic claim that all fridge-freezers behave alike. The refrigerator appearing cool can conceal a freezer problem.
A useful next step
Check the climate class and actual location conditions. Seek suitable placement advice rather than adding improvised heaters or forcing extreme settings.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.