Should I be worried about my iPhone?

So not long ago, I had a message on my iPhone saying "you must change your pass-code within the next 60 minutes" (the 4 digit number)

So I went along with it and changed it, but I'm not sure if it a virus or malware or something. I have never seen it come up before and it has me worried. Has anyone else had this? And any help is nice, thank you.

Added (1). it was like a pop up on my home screen

Added (2). and it was the pass-code for when you lock your phone and have to enter the pass code to unlock it.

Change it to a number you only know… That is a scam, so if these people steel it, they have your code.

Change your pass-code for what? I always ignore any text or email asking me for information or clicking here to change enter anything. If I get an email or text from say, my bank, I go to my NORMAL login for that bank to see what messages (if any) pop up. 100 out of 100 times, it will be a phishing or scam text/email.

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