We are experiencing few cases in which we received the signing completion callback more than once in case of In person signing.
Eg.: On sandbox for packet ID 9tICttbBe8xTghOAXD_00JM85YU=
We received the callback for final signer signing completion on 10/05/2018 at 1:13:31 pm EST and same callback again at 1:13:35 pm EST.
Sorry for the late reply. First to confirm with you, when you talk about “received the signing completion callback more than once”, do you mean “PACKAGE_COMPLETE or so called Transaction Completed” event? If so, I’ve tested for couple transactions with in-person signing and can’t reproduce the issue. And have you made a ticket with our support team? If so, you can share the ticket number to me and I can follow up the case for you!
And on the other hand, can your application make some checking mechanism to prevent getting effected by duplicated received callback notification? For example, every time when you receive the package complete notification, you can check the status of package first.