Can you try
1) disabling caching
2) disabling redirection like SH404 or SEF urls
3) verify that your secret key in your LinkedIn application is correct.
4) Looking at the browser developer tools network calls, it looks like your redirection URL is probably set correctly in the application, but can you doublecheck your application settings by following the
LinkedIn application setup guide
.
Try these suggestions and let us know if there's any improvement.
-Melissa