Commission is earned on completed Experiences. So if a booking is cancelled or refunded before the Experience takes place, no commission is due on it.
Why this is how it works
Your commission is tied to a traveler actually enjoying their Experience — not just booking it. If the Experience doesn't happen, there's no completed booking for commission to be based on.
In practice:
A booking that's cancelled before the Experience — no commission is earned, since the Experience never took place.
A completed Experience that's later refunded — if a completed booking is refunded, the related commission is voided.
What this means for you
Most of the time, this is straightforward: the bookings that complete are the ones you earn on. Cancellations are a normal part of travel, and an occasional cancelled booking simply doesn't convert to commission — it's not a penalty, just the nature of earning on completed Experiences.
You'll always be able to see the status of your referred bookings, so there are no surprises about which have earned commission and which haven't.