Only allow a user to register if they already booked a specific service

Hi!

So I'm using MS Booking to allow users to register training sessions with our staff. There are three training services they can choose from when they are registering. Is it possible to only let them book "Training 2" if they already booked for "Training 1"? Then "Training 3" if only they booked "Training 1" and "Training 2" already?

Thanks!