Thanks! (Now if I only knew what that meant in context of AMS ads... Sounds like they are blaming me for using something of theirs wrong...)
That message is showing for me too, not only you, so you didn't do anything wrong
I'm pretty sure the UI ('User Interface' as LSMay noted, not Doglover's one, although that may be why the data's having issues, lol) is what we first see when we login to AMS. The billing statements are probably the data found by clicking the 'Billing History' link in the upper-right menu (which seems to be higher than what the actual amount should be).