Is this after using the “Upload save” menu item on a previous character to transfer it to the XB1? If so, as long as you have already downloaded that save in the Handsome Collection version, you are fine - the in-game upload/download system only transfers a single save at a time, and only one way between the 360 and the XB1.
If you’re trying to do anything other than transfer a save from 360 to XB1-Handsome Collection, do not use the in-game menu since it’s only designed for the one thing.
I don’t have the handsome collection version It’s the backwards compatible Xbox 360 version I’m running on my Xbox One.
In that case, the saves should be in the sync folder, and you should not be using the in-game upload/download menu at all. Any saves should automatically be created locally and synced to the cloud without any intervention on your part.
If you should at some point in the future get the Handsome Collection (worth it for the 60 fps and improved graphics so keep an eye out for a sale), then you can use the in-game upload/download to transfer saves from one version to the other. That is all that menu is for though.