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.
If you want to update that device.. You will have to go to this page
And follow the instructions.. Its going to t ake a USB or SD card to purchase and transfer the update.
But most likely, you need to follow the steps at the bottom of this page to update the software of the Kenwood DX9990HD first
So use this link to update the software first.. And once you have done that, you wont have any issues updating the maps afterwords.
Let me know if you get stuck or run into any issues.
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.