This may happen for several reasons. But before we dive in, please check:
#1 - the name of the Google Calendar where you've blocked off slots
If slot is added to calendar that is different than the one connected in iClosed, it will not be possible to block off slots in the scheduler
#2 - double check if you've added slots in sub-calendar (e.g. Family, or Private)
If the slot is not added to main calendar, iClosed will not be able to block off slots
In case you haven't find a root cause in any of these two scenarios, please proceed with the troubleshooting guide:
#1 - Google Calendar in which slots are added is not connected with iClosed
Feel free to add your private calendars in 
iClosed as well, to ensure slots booked in private calendar are blocking the time for you to take calls. Follow the standard flow:
Navigate to Calendar Connections under
AI Scheduler on the left side menuClick the "Connect" button
Sign in with Google window will open and click Continue to proceed
Next window will pop up where you need to accept iClosed
"Select all" to grant the necessary permission and click the "Continue" button to complete to connect your calendar with iClosed
The primary calendar you've added will be selected as the one where Events will be stored and from which Google Meet link will be pulled.
Doublecheck and set what calendar is the primary one for the Events and edit if needed.
#2 - Google Calendar is connected, but not included in "Check for conflicts" iClosed
If all of your calendars are connected, maybe you didn't include secondary calendars in conflicts check.
While you're in Calendar Connections
Check for conflicts section → and hit "Edit" button
Mark or unmark calendars to be checked against Availability conflicts
If you would like to turn on all calendars for Conflict check, have all boxes checked.
#3 Google Calendar appointment status
In case you have a Google Calendar event that should be impacting your availability, but it's not showing in iClosed as taken slot, please navigate to Google Calendar and follow next steps:
Locate the event in your Google Calendar and click on it
Click on the pencil to edit the event
make this event "Busy" if you would like to affect your iClosed availability
Hit "Save"
iClosed will then automatically count you as "unavailable" for this particular time slot, depending of the choice.
