Draw a sequence diagram for the following situation. You may apply loop fragment or option fragment.

Once the customer is logged in, s/he can book any upcoming workshops. Initially, Bob sets the capacity for each workshop to 20 dancers. Once 20 bookings are made, any new bookings will be rejected, but the person is added to a waiting list. The headteacher and Bob will receive a notification (via email and text message) and can increase the number of sign-ups for the workshop manually, either immediately or at a later stage. The increase is only possible to a maximum of 25 places to comply with the studios health and safety regulations. Subsequently, more places open up for booking and the dancers on the waitlist will be notified. Once they have confirmed their interest in a particular workshop, they are automatically signed up for it.