We are aware of a problem where codes recently activated show as expired even when the product is active and ready to be used.
Our development team is working on a fix. We apologise for any inconvenience this might cause.
Even if your students see the 'Expired' message, they can still access tests after you assign them. After that, they can go to ‘My assignments’ or ‘My homework’ to access their tests.
If ‘My assignments’ or ‘My homework’ is not visible to them they may need to join your class or you may need to create an assignment for the test.