Turning the fridge colder does not authorise extending a food's use-by date. Follow the product's date and storage instructions rather than using an appliance setting to create a new deadline.
What the observation tells you
Use-by labelling concerns safety under the stated conditions. A temperature adjustment made today also cannot establish how the food was stored earlier. The fact that another product has a longer life does not provide evidence for this one.
A useful next step
Plan to use or freeze suitable food within the applicable instructions. If the date has passed, follow official food-safety guidance; do not taste it as a test. Report fridge problems separately from the decision about an expired item.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.