I’ve accidentally uploaded the wrong document into the wrong question
The short answer questions and uploads are NOT submitted to us for marking until you press the 'Submit my assessment' button on the very last page. As long as you have not already submitted the complete unit/cluster to be assessed then you can easily just delete the file and upload the new/correct file, or alternatively, overwrite your answer in a short answer question.
* See how do I delete uploaded files?
* See how do I upload files?