On my website, when you click the red Schedule button to make an appointment, the software I’m using is called SimplyBook.me. I’ve been using the free version for several months and it works well for me. There are lots of great upgrades available too, if you need them! I am an affiliate for their software. If you take my referral and decide to make a purchase from them, I will earn a commission. However there is a free version that you can use indefinitely, so check it out!