How to fix the Audi A4's air conditioning?

My Audi A4's air conditioning is not blowing cold air. How can I fix this issue?

First, check the refrigerant levels in your car's air conditioning system. If they are low, you may need to get it refilled. You can also try changing the air filter in your car, as a dirty filter can restrict airflow and affect the cooling. If these troubleshooting steps do not work, it is best to bring your car to a certified Audi mechanic for further diagnosis and repair.