sat nav updates

[Chief HLH]

Is there any way to update the maps in my A3 TDI on a 17 plate, without having to pay my local Audi main dealer £250?

I bought a TomTom sat nav a couple of years ago and that came with lifetime map updates. Google maps on my phone is always updating itself. So why do I have to pay Audi £250 for the privildge?

This is my second A3. and the first with MMI sat nav included