Hi and welcome to the forum!
I think the person you have pinged in your post will not reply any time soon since his last visit was almost ten years ago.
Please log in to your Steinberg Account and see if you have a valid Groove Agent license. Once you bought and activated GA its license does not expire, so if you once owned a license and did not sell it than it will still be there.
The Invoice of 170€ sounds fishy to me.