If you use Google Calendar to schedule appointments, you know it can be a pain when you get double-booked.
Sometimes it happens when you know you’ve added all your existing appointments to your calendar, so it’s extra frustrating and confusing!

One of the most common reasons we see for getting double-booked, especially when you’re using an external scheduler like Calendly, Acuity, etc., is putting an All Day Event on your Google calendar. When you first create an event, Google marks you correctly as Busy. As soon as you change it from a timed event to All Day, though, Google changes your availability from Busy to Free. This leaves your day open to be scheduled, even if it’s not what you intend!

How to fix?

With the affected calendar entry open, scroll to the bottom, where the availability is located. Click in that area and change the Free dropdown to Busy, then save the updated entry.

Now you are all set!