First, there should be no monthly charges - either from this site or any Garmin based site for maps, so if you see any such offers (with monthly charges), you can decline those offers.
Next, it MAY be that your device was NOT "registered" or identified with the Garmin site, OR you landed on a different site altogether.
So if you want to update the maps, I would suggest that you get the CURRENT Garmin program that does the updates installed on your computer (its called Garmin Express), run that program, and then connect your device via the USB cable - to see what is offered. I have the link to where you can get that program below. There is even a video showing how to use the program and when to connect the device.
If you had registered the device with Garmin (when purchased), that program SHOULD recognize that the device is registered, and be able to offer any map updates available.
Please try to get that program on to your computer, run it, and then connect the device to the computer when the program asks to do that.
Then let me know what you see what you do that.
Thanks, ***** *****
P.S. As for time zone, I'm in the Pacific Time Zone (West Coast of USA).