Extra canonical in middle of integration

Hello all,

We’ve encountered a strange anomaly in our XPI system last week. We have an integration to create an IDOC and write it on the SAP AS400 machine. This integration is live for about 6 months now.

Last week, 1 order IDOC was written to SAP twice (and processed twice by SAP)
I searched the logs and I found 2 write-operations that were executed, but more importantly: 2 canonicals carrying the same information (about the same order) that arrived at the writing part of the integration. 1 canonical I could trace back through the whole integration (using the activationID and enqueue-time) but the 2nd canonical seemed appear out of nowhere. The code in the activationID is different from the other canonical, as well as the enqueue-time… Does anybody have an idea where this 2nd canonical could come from?