Freestyle Libre 3 is no longer compatible with iOS 18.1 update

Abbott has a terrible track record of compatibility when updates, even minor updates are released.

They cut corners and take shortcuts in the development process.

You may want to look into a different brand of CGM.

Contact the makers of the device.

It is entirely their responsibility to ensure ongoing compatibility.

Yes, Abbott who is the maker of FreeStyle Libre admits there is an issue but are dragging their feet to fix it. Many people have complained about this.

You might have a look at Dexcom's products, they all work fine with the latest versions of iOS 18.