We have identified the change in the Infusionsoft API that caused a duplicate request error to be returned when the same data was sent into the ContactService.addWithDupcheck method with 5 minutes of each other.
We are going to fix this issue so that if you submit a duplicate request, you’ll get the same contact id back as you did the first time you sent in the data.
If you would like to receive an email notification when we have resolved the issue please navigate to the known issues page (http://knownissues.infusionsoft.com/) Find “ContactService.addWithDupChecking isn’t allowing duplicate checking to be done within a set amount of time” and choose “Report this issue for your app”. Fill out the form and you will be notified when this issue is resolved.