Unable to delete email address created with SIS upload

Community Member

We have been testing adding email addresses using the Canvas API in our test environment.  I found that I'm unable to delete certain email addresses using the UI and acting as a user, even when the email address is not set as the default. 

I don't have a need to delete email addresses at this time, but I am just wondering why this would happen.  If I'm unable to delete an email address using the UI, even when it is not set as the default, can I delete the communications channel using the API?