The section in the blog suggest we can update existing features:

For this function to work, one will need to be able to display existing corresponding data when a feature is selected, however, I am unable to get this to work:


And if I submit a survey against this same asset, I end up creating a new feature with the same ASSETNUM. This is not updating existing feature.
I am unable to find information on how I need to design my XLS form built from an existing feature service so that it knows to draw information from existing features once the feature is selected.
Please advice how I can go about setting up this ability. Or at least let me know this is not possible so I can proceed to find alternative way to built my form.
Thank you
SW