Final Notice: Your Account Will Be Deleted

Hi,

I have such problem:
I have only one Garmin account.
On this account I changed my email address to a new one quite a long time ago, and with this email I log into the account every day.
Now Garmin noticed the lack of logging in with the old email and wants to delete my account, I got a warning to the old email address that the account will be deleted soon (I wonder how my old email still appears in their database since I changed it)?

The support not very helpfully replies me with articles from the support site that in order not to lose your account you have to log in to it :-/
I don't know what to do because I wouldn't like to lose my account?