App crashes when tapping on WKWebview textfield

Question

Hi I am working on upgrading Xcode project from iOS 13 to iOS 14 and using xcode 12.1 When I run the application webview will be opened inside app and get login screen. When I tap on textfield app crashes with below error. Xcode is not showing where it is crashing exactly I tried Exception breakpoint also not able to identify.

-[NSConstantIntegerNumber length]: unrecognized selector sent to instance 0x1fae7fd20
2020-11-27 16:59:31.436225+0530 XYZApp [527:40363] *** Terminating app due to uncaught exception 
'NSInvalidArgumentException', reason: '-[NSConstantIntegerNumber length]: unrecognized selector sent 
to instance 0x1fae7fd20'
*** First throw call stack:
(0x1a669b114 0x1b9f37cb4 0x1a65ab9b8 0x1a669d758 0x1a669f6cc 0x1a7841754 0x1043fb8b0 0x1043fb8dc 
0x1eb5e3960 0x1eb5e1c54 0x1a6588ca0 0x1aa7e7264 0x1aa88bb60 0x1aa8613f4 0x1aa78e3a8 0x1aa84b56c 
0x1aa834b70 0x1aa852514 0x1aa85edac 0x1aa7b0d40 0x1aa7c4d50 0x1aa7b7d88 0x1af1f8198 0x1af1f9480 
0x1eb97995c 0x1af1f4ce8 0x1af165a2c 0x1af1663f4 0x1a8ae74bc 0x1a8a2b338 0x1a8a2a5a8 0x1eb9987d8 
0x1a8a2c628 0x1a8a2fbfc 0x1eb9982a4 0x1a8a33258 0x1eb9981fc 0x1a8a34cb4 0x1eb998050 0x1a91aee90 
0x1a91ae6d8 0x10505fdb8 0x1050615fc 0x10506fa6c 0x1a661ac30 0x1a66150e8 0x1a6614200 0x1bc791598 
0x1a8eddbcc 0x1a8ee31a0 0x1042f727c 0x1a62f3588)
libc++abi.dylib: terminating with uncaught exception of type NSException
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '- 

[NSConstantIntegerNumber length]: unrecognized selector sent to instance 0x1fae7fd20'
terminating with uncaught exception of type NSException