How to reset the MMI system on Audi A3?

I recently changed my car's battery and now the MMI system is not working properly. How do I reset it?

To reset the MMI system, disconnect the car's battery for 30 minutes and then reconnect it. This should do the trick. If not, try resetting the MMI system through the settings menu.

You can also try pressing and holding down the power button for 10-15 seconds to reset the MMI system. It's worked for me in the past.