In my case, when I try to block calls on iOS 26, the blocking doesn't occur; the scenarios seem intermittent. If I create two CallDirectory extensions, the first blocks the numbers, but the second doesn't. Interestingly, the extension marks the number as suspicious. There's also a case where, on iOS 26 on an iPhone 16 Pro, the functionality doesn't work at all. I'd like to know if there have been any changes to the use of CallKit in iOS 26, because users of my app on iOS 18 and below report successful blocking.