Where to find my catalog upload area
The upload area can be found under “Catalogs” → “Uploaded”.

You will only see the catalogs that have been assigned to you. To find the right catalog container, you can search for a specific catalog by entering the full catalog name or just a part of it in the search field.
In the catalog list, the catalogs are sorted by catalog status.
After clicking on one catalog name, you will find the upload button in the top right corner
