In order to determine exactly what to enter in the 'Name field', you can open the .dbf file in Excel.
To do so, in File Explorer head to the location of your unzipped shapefile and locate the mandatory .dbf file. If your shapefile is zipped/compressed, make sure to unzip (right-click > Extract all...)
Once located, right-click and head to Open with > Excel
If you don't see Excel as an option, click 'Choose another app'. If you still don't see Excel, or you can't locate Excel on your system, simply open excel separately and once opened drag and drop the .dbf file from File Explorer into Excel.
When you have your .dbf file opened in Excel, you should see a column that clearly contains the names of the custom areas your shapefile will create. The header of the column is what we will need to enter in our name field.
Please note: This name field is case sensitive, so please double check before uploading/entering.
In this example, we need to enter 'wd17nm' into the name field
In another example, you will need to enter 'NAME' in the name field.