If you want to assist a customer in canceling a lesson or registering a makeup lesson just follow this procedure

  1. Find the person you want to assist
  2. Under 'Registration' click on Pay (any of them)
  3. A new window opens
  4. You are now in that persons online account
  5. Click on 'Menu' and choose 'My Bookings'
  6. Cancel or register the desired lessons
  7. Logout via 'Menu'

That's it!