Is my iPhone being hacked?

I have been receiving annoying text on my screen as though someone is trying to hack my iphone

the text that I have been receiving for the past two weeks are as follows. I receive these messages

on my calendar. Even the lady from Apple could not help much by chat . I have already tried to delete

the calendar but the message keeps coming back. What can I do ?

The messages are as follows:

"Your calendar might be jailbroken". or. "Your iphone might be infected to repair click the link"

"upcoming event". etc. Please advise what needs to be done.

Thanks

[Re-Titled by Moderator]