When an expense has the status "duplicate", it means the file you uploaded was identified as a file that already was uploaded before based on a unique stamp that exists on every image file. Rydoo will ask you what action you want to take for the uploaded receipt.
By clicking on the relevant expense line:
You will go into the detail of the expense, where you see the uploaded image and where you can choose to "Keep" or to "Delete" the receipt.
By clicking on "Keep" the image will be made available again for editing and you can fill in the details.