I have received this report through firebase analytics(Crashlytics) and I have no idea what it is. Would you help me? The problem is only in iOS 14. (iOS 14.0.0, 14.2.0) There is no such case in versions below iOS 14 crash_info_entry_0 BUG IN CLIENT OF LIBDISPATCH: Unbalanced call to dispatch_group_leave() Stack trace Crashed: Thread #1 EXCBREAKPOINT 0x000000019836f7f4 Crashed: Thread 0 libdispatch.dylib 0x19836f7f4 <redacted> + 36 1 libdispatch.dylib 0x19833d8c4 dispatchgroupleave + 126 2 ??? 0x754b330102689c00 (Missing) 3 Life4MePlus 0x102682b8c -[AISynchronizationOperation main] + 38 (AISynchronizationOperation.m:38) 4 Foundation 0x199a9c0f0 <redacted> + 864 5 ??? 0x0 (Missing) 6 ??? 0x221c4e81dfc97800 (Missing) com.apple.main-thread com.apple.main-thread 0 libsystemkernel.dylib 0x1c4643dd0 machmsgtrap + 8 1 libsystemkernel.dylib 0x1c4643184 machmsg + 76 2 ??? 0x4b112781986bac00 (Missing) 3 ??? 0x31204581986b4e00 (Missing) 4 ??? 0x0 (Missing) 5 ??? 0x0 (Missing) 6 ??? 0x0 (Missing) 7 ??? 0x0 (Missing) 8 ??? 0x0 (Missing) 9 libdyld.dylib 0x19837be60 <redacted> + 4 Thread #2 Thread 0 libsystemkernel.dylib 0x1c46685bc workqkernreturn + 8 1 libsystempthread.dylib 0x1dfc90954 pthreadwqthread + 352 2 ??? 0x5d3bd101dfc97800 (Missing) Thread #3 Thread 0 libsystemkernel.dylib 0x1c46685bc _workqkernreturn + 8 1 libsystempthread.dylib 0x1dfc90954 pthreadwqthread + 352 2 ??? 0x0 (Missing) Thread #4 Thread 0 libsystemkernel.dylib 0x1c46685bc _workqkernreturn + 8 1 libsystempthread.dylib 0x1dfc90954 pthreadwqthread + 352 2 ??? 0x3453b581dfc97800 (Missing) com.apple.uikit.eventfetch-thread com.apple.uikit.eventfetch-thread 0 libsystemkernel.dylib 0x1c4643dd0 machmsgtrap + 8 1 libsystemkernel.dylib 0x1c4643184 machmsg + 76 2 ??? 0x0 (Missing) 3 ??? 0x61681c01986b5000 (Missing) 4 ??? 0x0 (Missing) 5 ??? 0x0 (Missing) 6 ??? 0x0 (Missing) 7 ??? 0x4a214b819b109000 (Missing) 8 ??? 0x15469a8199a9c100 (Missing) 9 ??? 0x0 (Missing) 10 ??? 0x0 (Missing) Thread #5 Thread 0 libsystemkernel.dylib 0x1c46685bc workqkernreturn + 8 1 libsystempthread.dylib 0x1dfc90954 pthreadwqthread + 352 2 ??? 0x0 (Missing) Thread #6 Thread 0 libsystemkernel.dylib 0x1c46685bc _workqkernreturn + 8 1 libsystempthread.dylib 0x1dfc90954 pthreadwqthread + 352 2 ??? 0x0 (Missing) Thread #7 Thread 0 libsystemkernel.dylib 0x1c46685bc _workqkernreturn + 8 1 libsystempthread.dylib 0x1dfc90954 pthreadwqthread + 352 2 ??? 0x0 (Missing) com.twitter.crashlytics.ios.MachExceptionServer com.twitter.crashlytics.ios.MachExceptionServer 0 Life4MePlus 0x10277e5dc CLSProcessRecordAllThreads + 376 (CLSProcess.c:376) 1 Life4MePlus 0x10277e5dc CLSProcessRecordAllThreads + 376 (CLSProcess.c:376) 2 Life4MePlus 0x10277ea50 CLSProcessRecordAllThreads + 407 (CLSProcess.c:407) 3 Life4MePlus 0x10276ee60 CLSHandler + 26 (CLSHandler.m:26) 4 Life4MePlus 0x10276a204 CLSMachExceptionServer + 446 (CLSMachException.c:446) 5 libsystempthread.dylib 0x1dfc8eca8 pthreadstart + 320 6 ??? 0x7c25b581dfc97800 (Missing) AFRKNetworking AFRKNetworking 0 libsystemkernel.dylib 0x1c4643dd0 machmsgtrap + 8 1 libsystemkernel.dylib 0x1c4643184 machmsg + 76 2 ??? 0x3713a981986bac00 (Missing) 3 ??? 0x0 (Missing) 4 ??? 0x684cc081986b4400 (Missing) 5 ??? 0x7237968199932000 (Missing) 6 ??? 0x6813c40199964800 (Missing) 7 ??? 0x452e2b010368f800 (Missing) 8 Foundation 0x199a9c0f0 <redacted> + 864 9 ??? 0x0 (Missing) 10 ??? 0x710e8a81dfc97800 (Missing) Thread #8 Thread 0 libsystempthread.dylib 0x1dfc97774 <redacted> + 6 com.apple.NSURLConnectionLoader com.apple.NSURLConnectionLoader 0 libsystemkernel.dylib 0x1c4643dd0 machmsgtrap + 8 1 libsystemkernel.dylib 0x1c4643184 mach_msg + 76 2 ??? 0x0 (Missing) 3 ??? 0x0 (Missing) 4 ??? 0x60677381986b4400 (Missing) 5 ??? 0x386bc00198f6d000 (Missing) 6 ??? 0x552580199a9c100 (Missing) 7 ??? 0x47378301dfc8ec00 (Missing) 8 ??? 0x0 (Missing)