The 502 error could be indicating that there was a hiccup with the connectivity or there could be some type of network issue. Can you please try again and let me know if the problem persists? Please check to see if your browser, computer and network are functioning properly. Also, check to see that your firewall is allowing traffic flow.
If the issue persists, please provide more information on the error you have received. Please send response request of the error received, screenshots and the Correlation ID. Please let us know if you have other questions.
Below are the steps to get the Correlation ID using a Google Chrome browser. 1>Open Chrome menu. 2>Click on More tools then Developer tools. 3>Check the box to Preserve Log for the Network Tab. 4>Then try to click on the add API link. 5>You can find the Correlation ID in the network log for add API call.