DataShare is a static view of the client's data. If DataShare is not showing the client's most recent data, then a new upload will be required.
If the data is still not up to date after an upload, then the client will need to confirm the accountancy package data they are using is up to date and is the correct data.
Every upload overwrites the previous uploaded data, uploading more than one company data to the same engagement can show incorrect data for that engagement. Please view this article for more information on this: Can I upload all my data sets to the same engagement?