iOS Webview input box change to emoji keyboard app crash

I am working with my web team, and I provide a webview to calling their web page. Inside the webpage there are some input box to fill-in information with user. When user change the keyboard to emoji. The app crash with

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSTaggedPointerString count]: unrecognized selector sent to instance 0xa00000000006e652'

How can I fix it on my side or any suggestion to my web team?