I have received warnings from Safari that some of my old passwords have been noted as compromised by hackers. It always recommends that I sign in to that website on my own to reset the password. I have never received a text saying this, and it seems very unlikely that any website would send you a text about your password. This sounds like a scam. Never click on a link in such messages. If you want to check or change your password, navigate to the website in question on your own to complete the task.