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.
Error Blocking Phone Numbers
Please check this out: https://developer.apple.com/forums/thread/800415
I guess it can be the same case
The call will not be blocked if an outgoing call was made to its number before. It will be blocked if we delete the outgoing call record from the Phone.app Recents
Can you test this scenario on your device please? I believe that if multiple people have this problem, Apple will prioritize fixing it
Thank you in advance