'-[BRACell attributedStringValue] is not implemented in BRACell'，Error reported using version 2.3.2

[vlay1314]

I added my own xlxs file and reported an error, the error is as follows：
*** Assertion failure in -[BRACell attributedStringValue], BRACell.m:333
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[BRACell attributedStringValue] is not implemented in BRACell'
*** First throw call stack:
(
0 CoreFoundation 0x00007ff8004cd571 __exceptionPreprocess + 242
1 libobjc.A.dylib 0x00007ff8000837e8 objc_exception_throw + 48
2 Foundation 0x00007ff800dd95e4 _userInfoForFileAndLine + 0
3 XlsxReaderWriter 0x000000010b3b6d73 -[BRACell attributedStringValue] + 1363
4 XlsxReaderWriter 0x000000010b3b67d8 -[BRACell stringValue] + 40
5 ContactsApp 0x0000000109a6859d -[CallViewController viewDidLoad] + 2797
6 UIKitCore 0x00007ff8052effee -[UIViewController _sendViewDidLoadWithAppearanceProxyObjectTaggingEnabled] + 80
7 UIKitCore 0x00007ff8052f60e6 -[UIViewController loadViewIfRequired] + 1342
8 UIKitCore 0x00007ff805211b2b -[UINavigationController _updateScrollViewFromViewController:toViewController:] + 159
9 UIKitCore 0x00007ff805211e5f -[UINavigationController _startTransition:fromViewController:toViewController:] + 210
10 UIKitCore 0x00007ff805213035 -[UINavigationController _startDeferredTransitionIfNeeded:] + 856
11 UIKitCore 0x00007ff805214495 -[UINavigationController __viewWillLayoutSubviews] + 136
12 UIKitCore 0x00007ff8051f0de2 -[UILayoutContainerView layoutSubviews] + 207
13 UIKitCore 0x00007ff8063bff3c -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 2138
14 QuartzCore 0x00007ff80b19a775 _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 527
15 QuartzCore 0x00007ff80b1a65a1 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 67
16 QuartzCore 0x00007ff80b0c5cf4 _ZN2CA7Context18commit_transactionEPNS_11TransactionEdPd + 706
17 QuartzCore 0x00007ff80b10082a _ZN2CA11Transaction6commitEv + 728
18 UIKitCore 0x00007ff805cfed8f __34-[UIApplication _firstCommitBlock]_block_invoke_2 + 34
19 CoreFoundation 0x00007ff800429dea CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK + 12
20 CoreFoundation 0x00007ff80042959d __CFRunLoopDoBlocks + 391
21 CoreFoundation 0x00007ff800423e7c __CFRunLoopRun + 940
22 CoreFoundation 0x00007ff8004236ed CFRunLoopRunSpecific + 557
23 GraphicsServices 0x00007ff8103ba08f GSEventRunModal + 137
24 UIKitCore 0x00007ff805cdf6ee -[UIApplication _run] + 972
25 UIKitCore 0x00007ff805ce416e UIApplicationMain + 123
26 ContactsApp 0x0000000109a3f686 main + 118
27 dyld 0x0000000109f023e0 start_sim + 10
28 ??? 0x0000000115ed7366 0x0 + 4662850406
)
libc++abi: terminating due to uncaught exception of type NSException