Most of the time, this happens because the customer has rescheduled using a Google link instead of using a Cowlendar link.
Warning
Recall that when a customer makes a booking they get the cowlendar email and the google invite notification (to add the event to there google calendar)
Any update made on Google by the customer won't be taken into account by Cowlendar.
Google does not communicate this with Cowlendar.
It is written in the event on Google Calendar not to use the google links to reschedule.
You need to trust the data from Cowlendar dashboard. This is the only place where everything is 100% accurate.
→ Broken Link