How to remove unlisted but subscribed-to internet calendars from the new outlook

Question

I am subscribed to an Internet calendar, but it does not appear anywhere on my list of calendars in the new Outlook. Although the calendar has a name, the name does not appear in Outlook. (It is a blank title. I only know what it is due to the content of the calendar).

I want to remove it, but it doesn't appear anywhere in my list of calendars.

Is there a configuration file somewhere that contains a list of internet calendars that I subscribe to, where I can simply remove it from the configuration file?