Crash in UNUserNotification

I'm working on a new application that uses the UNUserNotification framework. I distributed the application to a few testers. One of them reports a crash at launch, occurring in Dispatch queue: com.apple.usernotifications.UNUserNotificationServiceConnection.call-out. All other users report the application working correctly and have reported no crash. The user is using an iMac Retina 5K, 27-inch, from 2017. He's running macOS 13.6 (22G120). The strange part is that he sent me a screenshot showing that my application does not appear under the Notifications of System Settings, which might explain the crash. The relevant thread that crashes is:

Thread 12 Crashed::  Dispatch queue: com.apple.usernotifications.UNUserNotificationServiceConnection.call-out
0   libsystem_kernel.dylib        	    0x7ff810ecd1e2 __pthread_kill + 10
1   libsystem_pthread.dylib       	    0x7ff810f04ee6 pthread_kill + 263
2   libsystem_c.dylib             	    0x7ff810e2bb45 abort + 123
3   libc++abi.dylib               	    0x7ff810ebf282 abort_message + 241
4   libc++abi.dylib               	    0x7ff810eb13fb demangling_terminate_handler() + 267
5   libobjc.A.dylib               	    0x7ff810b857ca _objc_terminate() + 96
6   libc++abi.dylib               	    0x7ff810ebe6db std::__terminate(void (*)()) + 6
7   libc++abi.dylib               	    0x7ff810ebe696 std::terminate() + 54
8   libdispatch.dylib             	    0x7ff810d64047 _dispatch_client_callout + 28
9   libdispatch.dylib             	    0x7ff810d6a200 _dispatch_lane_serial_drain + 769
10  libdispatch.dylib             	    0x7ff810d6ad6c _dispatch_lane_invoke + 417
11  libdispatch.dylib             	    0x7ff810d753fc _dispatch_workloop_worker_thread + 765
12  libsystem_pthread.dylib       	    0x7ff810f01c55 _pthread_wqthread + 327
13  libsystem_pthread.dylib       	    0x7ff810f00bbf start_wqthread + 15

Does anyone have any idea of what's happening?

The crash is caused by an uncaught exception in com.apple.usernotifications.UNUserNotificationServiceConnection.call-out queue. It is essential to inspect your code to identify and address any instances where exceptions might be thrown.

Crash in UNUserNotification
 
 
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