Code is rejecting submission

For some reason we aren't able to submit our code. The reason they give is:

ITMS-90809: Deprecated API Usage - New apps that use UIWebView are no longer accepted. Instead, use WKWebView for improved security and reliability. Learn more (https://developer.apple.com/documentation/uikit/uiwebview).

We've looked through the code and cannot find any offending. We are unsure how to proceed. Any help would be greatly appreciated. Thank you
Well, If you are sure that you never used any Deprecated API usage you can submit an appeal in App Store Connect. And you may want to check out the Human interface Guidelines to see if there is anything else that you missed. If you need more help just reply and I will see if I can help!
Hi, Thank you for the response. The current dev team couldn't figure it out and we've been going in circles for weeks. Can you help?
Are you using any 3rd party APIs/libraries?

If so, contact the authors of those products for updated/compliant versions, then use them.
Code is rejecting submission
 
 
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