There are two things to check if a client is trying to book an appointment through your website and no times are available.
Your Google calendar
Jupiter syncs with your Google calendar to work around existing events you have. Your booking website will only show the times slots you are available. Double-check to make sure that your Google calendar is clear of any other events. We recommend syncing your Jupiter account with a separate work calendar.
Please note: any changes to your appointments should be made directly in Jupiter. If you make any changes to your Google calendar, such as rescheduling or canceling an appointment, Jupiter's calendar will not be automatically updated.
Check to see if your availability is correct. To set your hours, please refer to the article: Setting my availability. There is currently no option to double-book appointments.
Clients will not be able to book within your minimum notice. If you set your minimum notice to 24 hours, clients will not be able to book for the next day. To make an exception, you will have to create an appointment on their behalf.