Microsoft Graph Throwing 403 Error for Calendar with Correct Permissions

Question

I am making calls to the Microsoft Graph "/users/{id}/events" endpoint as an apllication with no logged in user but getting 403 forbidden returns. I have:

• Checked that I have all of the correct application permissions (I have added Calendars.ReadBasic.All, Calendars.Read and Calendars.ReadWrite to be sure, https://learn.microsoft.com/en-us/graph/permissions-reference#application-permissions-10)
• Checked that the permissions are contained in the token I am using
• Checked there are no Application Access Policies that are preventing access using the Get-ApplicationAccessPolicy cmdlet in Powershell
• Subsequently explicitly allowed the application access to specific mailboxes for the app

I am able to retrieve a list of calendars and am able to list messages from the inbox of the user but when I try to load a list of events I get "Access is denied. Check credentials and try again." Are there permissions that I am missing?