Apppoint type catorogies (URGENT) - also for better UX in APP

I am sure this must appear as a long list on an app—we have so many appointment types for treatments; just in chiro, we have a membership, PAYGO, and three pre-pay plans. In my clinic, we also run three similar appointment types: osteo, physio, and massage, which are sports and Swedish. Each one of these has three durations, meaning six app types for massage alone.
My CA is remarkable as they regularly rifle through this long list and know where things are, but clients can not.
IDEA: have their popular types of session at top of list: saying something like last app you had - want to rebook this? or explore other appointments offered at the clinic