Calendar hack

Hi

I have recently had an email to my junk folder from i.imgur.com which I did not open. Annoyingly this then set up an appointment in my calendar over four days that reads “your personal information is no longer protected “ I can’t remove it or delete it and I am loathe to decline or communicate with it. Has anyone ever seen this type of spam before? I have had numerous spam emails from this source and don’t know how to block them. Any help would be greatly appreciated 🙂