That's not an error.
When you subscribe the system sends you cards a couple of days before they're added to your collection. They're the ones labelled 'Coming Up'. You can download them but you can't play them until the day they're added to your collection.
One little thing I've noticed is that, for me, the card appears in the 'My Collection' screen on the website from Paris midnight, but it's not added to 'my collection' in the VG software until my local midnight.