I have a PHP application and am using Auth' n Auth for authentication. When I click I agree on the eBay consent screen, it hits my callback URL as expected. However this is what is returned - http://mycallback.url/?ebaytkn=&tknexp=1970-01-01+00%3A00%3A00&username= As you can see the ebaytkn is null and the tknexp is 1970 which as already happened. The solution is working in Dev but not production. Any idea why this is happening?