Jezzam gives you full control of your own booking rules and policies.
To change your cancellation policy:
1) In the Admin Panel go to Settings > Booking Rules
2) Select an appropriate cancellation policy under “Cancellations and changes”
3) Click “Save”
If you manage both Public Bookings and Member Bookings you will see a section for each of these under "Cancellations and changes". This allows you to set different policies for these groups if you need these.