You can set this yourself at
1. Settings
2. Calender
3. Online appointments
4. Enter the amount of days in "Days clients can cancel before the appointment"

5. Enter the amount of days in "Days clients can move before the appointment"
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👉 example: 3 days
= customer has an appointment on Friday; can move or cancel by Monday at the latest
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Tip:
You don't want your clients to be able to move or cancel an appointment at all?
The higher you put the number of days, the harder it will be to cancel or move.
Example: if you put it on 365 - they will only be allowed to move and/or cancel if they have made the appointment for a year in advance
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