ios crash: unrecognized selector sent to instance

[niceseee]

2020-08-25 13:50:30.553941+0800 Runner[96932:1744793] [core] "Error returned from daemon: Error Domain=com.apple.accounts Code=7 "(null)""
2020-08-25 13:50:30.618838+0800 Runner[96932:1744600] -[NSNull length]: unrecognized selector sent to instance 0x7fff8062d200
2020-08-25 13:50:30.646217+0800 Runner[96932:1744600] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSNull length]: unrecognized selector sent to instance 0x7fff8062d200'
*** First throw call stack:
(
0 CoreFoundation 0x00007fff23e39f0e __exceptionPreprocess + 350
1 libobjc.A.dylib 0x00007fff50ad79b2 objc_exception_throw + 48
2 CoreFoundation 0x00007fff23e5ac34 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
3 CoreFoundation 0x00007fff23e3e90c forwarding + 1436
4 CoreFoundation 0x00007fff23e40bf8 _CF_forwarding_prep_0 + 120
5 Foundation 0x00007fff259615bc -[NSURL(NSURL) initFileURLWithPath:] + 68
6 Foundation 0x00007fff25961f63 +[NSURL(NSURL) fileURLWithPath:] + 33
7 video_thumbnail 0x000000010e08f598 -[VideoThumbnailPlugin handleMethodCall:result:] + 1880
8 Flutter 0x000000010c4beb16 __45-[FlutterMethodChannel setMethodCallHandler:]_block_invoke + 104
9 Flutter 0x000000010bcca2ba _ZNK7flutter21PlatformMessageRouter21HandlePlatformMessageEN3fml6RefPtrINS_15PlatformMessageEEE + 166
10 Flutter 0x000000010bcced58 _ZN7flutter15PlatformViewIOS21HandlePlatformMessageEN3fml6RefPtrINS_15PlatformMessageEEE + 38
11 Flutter 0x000000010c0089df _ZNSt3__110__function6__funcIZN7flutter5Shell29OnEngineHandlePlatformMessageEN3fml6RefPtrINS2_15PlatformMessageEEEE4$_33NS_9allocatorIS8_EEFvvEEclEv + 83
12 Flutter 0x000000010bcd6d37 _ZN3fml15MessageLoopImpl10FlushTasksENS_9FlushTypeE + 117
13 Flutter 0x000000010bcdb7c6 ZN3fml17MessageLoopDarwin11OnTimerFireEP16__CFRunLoopTimerPS0 + 26
14 CoreFoundation 0x00007fff23d9e634 CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION + 20
15 CoreFoundation 0x00007fff23d9e2ce __CFRunLoopDoTimer + 1038
16 CoreFoundation 0x00007fff23d9d92a __CFRunLoopDoTimers + 282
17 CoreFoundation 0x00007fff23d9857e __CFRunLoopRun + 1950
18 CoreFoundation 0x00007fff23d97ac4 CFRunLoopRunSpecific + 404
19 GraphicsServices 0x00007fff38b2fc1a GSEventRunModal + 139
20 UIKitCore 0x00007fff48bc7f80 UIApplicationMain + 1605
21 Runner 0x000000010b9fdfeb main + 75
22 libdyld.dylib 0x00007fff519521fd start + 1
23 ??? 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)