Hello Jason Henry,
I understand you are trying to link Calendly to an O365 email address but getting "Approval required" screen and unable to find those consent requests.
To find the assigned administrator who can approve consent requests, you can check below:
Go to Microsoft Entra Admin Center -> Enterprise applications -> Consent and permissions -> Admin consent settings -> Click on Users to find reviewers
Now, I tried to link Calendly to an O365 email address from one test user account and got "Approval required screen" as below:
Once justification is added and clicked on Request approval
option, I got below screen:
To approve these consent requests, login to Microsoft Entra Admin Center with that Reviewer user account having Global Administrator access:
Go to Microsoft Entra Admin Center -> Enterprise applications -> Under Activity -> Admin consent requests -> Select Calendly application -> Review permissions and consent
After clicking on "Review permissions and consent", approve consent as below:
Once consent is approved, you will be able to link Calendly to an O365 email address successfully.
Hope this helps to resolve the issue!
Please do not forget to "Accept the answer” and “up-vote” wherever the information provided helps you, this can be beneficial to other community members.
If you have any other questions or are still running into more issues, let me know in the "comments" and I would be happy to help you.