Calendar invite issue resolved on my own

A very simple task which needs only a few clicks did not work. Nothing really helpful online. So called Apple support, the female advisor answered the call with strong attitude, after repeating my simple question twice she asked a bunch of BS questions such as when the issue started, and told me in a condescending tone “so the issue is not that you can’t send out, it’s the invitees do not receive it.” I said I don’t know whether it sent out, there is no confirmation message. Then asked what the iOS version on the invitees’ phone, I told her it’s the latest since the invitees are a cybersecurity tech. Then she questioned me what’s the latest iOS version. So either she was once again engaging her mouth with condescending words or she as an Apple support person does not really know their latest iOS release is. It’s obvious that she is clueless, instead of admitting that, she just threw some nonsense to me to fill up her time until I gave up. The support person on the live chat was very professional, however after going back and forth, finally told me without iCloud + subscription sending invite on iCalendar is not supported. Well, the article on Apple site didn’t state iCloud+ is one of the prerequisites. Thanks for reading up here if you did. I resolved it by simply turning off calendar on the other two accounts “yahoo” and “Gmail”. Both techs saw that I had 3 accounts under calendar settings. Apple is supposed to be the top notch company, but the two techs I have encountered for this simple issue certainly aren’t not.