It is not possible to submit only one document in an xCP environment.
When you submit documents individually for classic categorization, the documents are added to a queue awaiting CIS server processing. They are processed as CIS server retrieves documents from the queue.
For classic categorization, make sure the taxonomies are synchronized.
To submit a document for CIS server processing:
Select the document that you want to categorize.
Select Tools > Submit for Classification.
Related topics: Submitting documents to CIS server