Choose multiple times on the same date when booking a package.

I offer packages of 5 or 10 lessons. I have a client who needs to be able to pay for a pack of 10 lessons, but also needs to be able to choose two slots on the same day. For example, she needs to be able to book two slots on Monday, one at 5 pm (1 hour) and the second at 7 pm (1 hour), and to be able to do this for 5 consecutive weeks. I need a way to allow a client to book more than two slots for the same date when booking a package.