I have lifetime maps included with my device. Not done an update for a while. I have started the MyDrive app, logged into my account, connected the satnav to my laptop, can see my model shown in the devices registered, but can't see where to click. I can see a 'How to Update' button that just leads me to instructions for all the above things I have already done. How do I now get it to update my maps from this point? I was expecting something like an 'update now' button but can't see one.