Approve this iPhone pop-ups won't stop on my Macbook

You don't say anything about the model phone and the system version it is running.

Even assuming it is a "bug", Apple tends to not update software for anything but the current and one previous system versions unless it is a security risk (and even then they don't go back too far).

By the way, nobody on this forum works for Apple so we can't speak with any real authority as to what they do, other than what we notice in using their stuff for years.

Refer to this page for Apple Support features ➔ Contact - Official Apple Support

Select from the presented options until you find a solution for your issue, or see if there is a chat or phone call contact method offered lower on the page (you sometimes have to narrow down the options multiple times before this is shown). If you do not see your issue, keep experimenting with any series of selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.

This page has telephone numbers for contacting Apple for support and service ➔ Contact Apple for support and service - Apple Support

I'll add that this is not a chat session, and we are all volunteers. We can't guarantee immediate responses.

Could it be related to this?

https://krebsonsecurity.com/2024/03/recent-mfa-bombing-attacks-targeting-apple-users/