Welcome to Justanswer.com, my name is Dustin.I'm sorry to hear about the issue you are having, I will do my best to help you resolve it.
You can get a map for England on your nuvi.. What I suggest, is ordering the map on a pre loaded SD card from garmin.. That way all you have to do is insert the SD card.. Then, go to settings, maps., map info and select the England map. And then you can easily use the new map without having to erase your Australia / N.Z. maps..
You can order the Sd card here https://buy.garmin.com/en-GB/GB/maps/on-the-road-maps/city-navigator-nt/city-navigator-europe-nt-u-k-ireland/prod8424.html
Before you order, make sure on the page above you click version and then choose SD card, as that will make the process a bit easier rather then having to download and install the maps on your device yourself.
If you have any further questions or concerns, let me know.
I strive to provide great service, and greatly appreciate a 5 star rating clicked and submitted when you are satisfied.. I always answer follow up questions.Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.
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