When checking your usage report, sometimes you might encounter Double Result Credit.
This document will clarify what it means.
Double Result Credit
In order to verify that all your data is uploaded correctly to our server, the device will not remove the data unless it gets a confirmation from our server that the interviews have been uploaded successfully. In some cases of network latency, data might be received by the server but the confirmation sent from the server to the device, did not reach it. In these cases the device resend's the interview - so it get's the confirmation from the server. Our server is designed to recognize this pattern behavior and removes the duplicate credit use for this account due to the duplicate upload. This process happens as a background process but is transparent to you as well - However, this will indicate the result has been re-confirmed and did not use duplicated credit, but a regular 1 credit as expected.