At least one uploaded document is missing for the following horse : ...

This message appears when information of the horse has been changed in the FEI database.
The rider or Person responsible need to upload images of the national or FEI passport before this horse can be entered in the FEI entry system for an upcoming show.

As the horse is already entered in the current show this message is 'For information only'

More information can be found on the FEI website:

https://howto.fei.org/content/7/67/en/how-to-use-the-fei-horseapp-to-upload-horse-documents.html