Error with Outlook integration for interview scheduling

[JakobDigranes]

Hi all

We have configured integration with Exchange Online for interview scheduling;
https://help.sap.com/docs/successfactors-recruiting/setting-up-and-maintaining-sap-successfactors-re...

And connection is successful, and scheduling is successful - however, nothing appear in mailbox for serviceaccount used, not in the mailbox of the person where interview is booked. Both are internal mailboxes. 

Anyone have any tips for troubleshooting, or another piece of documentation other than the one linked? 
Enterprise app have all permissions configured, and administrator have consented. Service accounts is licensed with Exchange Online P2

[JakobDigranes]

Some extra information / question. 

I reckon all this is played out in the backend with enterprise app and API access, but then someone mentioned that booking meetings in calendars directly for employee - manager conversations does not work as they use new Outlook - which has some limitations in terms of .ics files. (from SAP support)

Anyone using this with new Outlook?