Reckon One users can have 1000s of bills a month to enter, human error may lead to bills being duplicated. To stop this from happening, Reckon One should notify the user if this reference has been used before.
A UK partner has said the lack of this functionality has lost us 40 clients. This has also been requested on the community: https://community.reckon.com/reckon/topics/stop-duplication-of-reference-numbers
This functionality exists, but a bug is stopping it from working correctly.
Bug to be fixed as part of standard QA process.