You can do so using the Sign-in Reconciliation report or the Hours Used vs. Hours Booked report.
This Sign-in Reconciliation report will give you the last 45 days of bookings and sign-ins and attempt to match them up. It does so by looking at who signed in, who the booking was for, and what date these were on. Your clients must be using the sign-in/sign-out feature for this report to pull the data.
This report will also give you the duration of the booking and the sign-in/sign-out period, and the difference between them. If one or the other is missing, of course, the difference is n/a.
If you have a client who has multiple bookings on one day, there may not be a one to one match between the signin sheet and the booking. In this case, you want to look at the 'in_at' and 'starttime' fields to match them up.
The Hours Used vs. Hours Booked report will give you the total difference in bookings and sign-ins for the month, for each client. This is helpful as a snapshot, so you can add a custom one-time fee or credit to your clients at the end of the month, as needed. It's smart to still spot check the Reconciliation report, in case a client forgot to sign-out one of those days.
To reconcile the difference, you have a few options:
Add the additional booking time to your client’s accounts as new bookings - Open the Signin Reconciliation report > click 'see on calendar' > create booking > assign to that client
Extend the original booking time to match the hours used - Open the Signin Reconciliation report > click 'see on calendar' > Click on booking > Edit
Add a one-time fee to the client's account for the additional amount at the end of the month (one-time fees are billed to the client within 24 hours) - Open the Hours Used versus Hours Booked report to see the difference > go Clients tab > client > Fees/Credits > Add > Custom Fee