Text message saying iPhone has been compromised

It is a scam. Do not respond to texts of those kind. Simply ignore those text messages and do not click on anything. If you have clicked on a link then things are still fine as long as you did not enter any of your username/password information.

Axel F.

See this Apple support link—>Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

This might also be useful—>Identify legitimate emails from the App Store or iTunes Store - Apple Support

You are welcome.

Axel F.