You can share an invitation link or a QR code to your course or stream through the 
menu. You can manually set its expiration date:
NOTE: Every time you enter the Manage Learners menu, the platform generates a new invitation link and QR code that you can send directly to your learners.
Your link has expired
Learners who will click on this link after its expiry will receive this page and will not be able to join your course/stream:
If you wish to allow these learners to join your course/stream, create a new link with new expiry settings and send it to them.