Can't delete SPAM meeting invitations from iPhone 13 IOS 17.1.2

I have an iPhone 13 running IOS 17.1.2 Yesterday I received an invitation to a SPAM recurring meeting. I chose 'decline' but the invitation stayed on my iPhone AND a second nearly-identical invitation popped up, then a third! When I click on any of the invitations, there is no option at the bottom of the screen to Delete or Decline the invitation. I've gone into Settings and could not find any unknown accounts, either in Passwords or Calendar. I can't seem to find any way in which these invitations are unique. Help! How can I get rid of them?