Booking App Schedule Cowlendar

Adding available time slots is way too hard. We do not do it often, and every time we try it, we need to reach out to the customer service. We already took notes, still, can not navigate to adding specific time slots on specific dates. This app is very very hard to use!!!
I wish Shopify would have another option other than Cowlendar App to add to our webpage as appointment scheduling app. We have been using it for over a year and extremely unhappy with it.