Hey there @khagerty - thanks for your topic, and sorry to hear this is happening! Firstly - check out our New User Guide when you get a chance. It’ll be so helpful as you get to know the platform that is Calendly! 

That said - let’s dig into your problem! So, it’s important to note that Calendly will only notify the Calendly host and the invitee of new bookings. There is currently not actually a way (within Calendly itself) to set it up so a secondary host is notified (or a secondary person at all!) unless you are using a Collective Event Type (in which case any/all hosts on a single booking will be notified as they are officially hosts on the booking).

When users write in asking how to set it up so that an additional person is notified of new bookings, we tell them to set up a forwarding filter within their own email address (whatever email they are receiving booking notifications for - this will be your login email address - where all notifications for new bookings are sent). 

It seems to me that you have, at some point in time, likely set up one of these forwarding filters within your O365 email account - and that forwarding filter is sending out an email notifying your colleague for each of these bookings. Please take a look at that and turn it off/cancel it if that’s the case, as we cannot access your email account in order to verify for you! 

If you are still unable to figure it out and do not find a forwarding filter, check out your O365 calendar settings to see if you have shared your calendar/certain bookings with your colleague that way. Still stuck? Please reach out to O365 Support here, as they’ll be the expert advice on this matter! 

I hope this helps!