Using Manager V16.3.74. There seems to be an issue with the numbering of Delivery Notes. Unable to edit the serial number of the documents and even if tried, the number keeps on increasing while updating the document.
Try updating your version. There was a bug that was fixed at v16.3.77 that may have been related. I don’t know for sure.
Thank you @Tut
I just updated the version to 16.3.77 and it solved the issue.