We have not received any other reports of problems with our custom/3rd-party Integration feature, which does seem to be working fine, so if you haven't changed any relevant settings in your E-junkie Seller Admin, we'd recommend troubleshooting things at your end.
If you could email the Transaction IDs of some affected orders to our Support team, we could ask Development to research those particular cases to see if any errors were returned when we attempted to post data to your URL for those orders:
https://www.e-junkie.com/ej/contact.php