This is not a problem with your webservice / webserver.
Starting this June, Apple expects applications to run on IPV6 networks. Apple has begun to reject Applications that do not match this.
NSURLSession, NSURLConnection, AFNetworking 3.x + IPV6 Support
If you use any other network libraries, use the link below to test IPV6 support http://www.brianjcoleman.com/tutorial-how-to-test-your-app-for-ipv6-compatibility/
If you encounter problems creating web requests when the application is running on an IPV6 network, you will have to upgrade / replace your network libraries with equivalent versions of IPV6.
Once you have finished testing your IPV6-enabled application, you can resubmit it to the application store for approval.
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