Sat nav problems

[Gethyn]

Hi is there anyone who can give me advice?

my sat nav doesn’t fully work as in when you put an address in sometimes a message will pop up saying ‘this address doesn’t exist’ or ‘send to middle of range’

now Ford has given me a new SD card to no avail and now they have turned around and said there’s nothing they can do??

surely I have some rights as the product was faulty to begin with? 

Its a focus 2015 newer model

thanks 

Geth