How do I stop notifications on my MacBook calendar app for a “calendar” that has been deleted?

I have a MacBook, and had a calendar named “Bills” in this calendar application with notification reminders for events which was deleted months ago. For some reason, even though the entire calendar has been deleted all together, I still receive pop up notifications for the recurring events. I tried to search for a calendar file that the app may be pulling from, but no results come up for it.