Unable to delete iCloud Calendar spam invitations on iPhone

Hi, suddenly a bunch of spam invitations (warning about iCloud storage) appeared in my calendar but when I try to delete them, I either get a pop-up message “my response can’t be received by sender” or the screen just goes back to the calendar view. How do I delete these? Have 3 calendars connected (Hotmail, Gmail, iCloud) and tried disconnecting the iCloud one, didn’t work. And didn’t see option in settings to view Accounts linked to iPhone calendar separate from other calendars (per some website instructions). Have a iPhone 23 with IOS 26.6.2. Help! And thank you!