If you're using the scanner tool in Nutshell, there's a delay between the contact being created from the card and all of the data elements being transcribed. So, if the zap picks it up before certain fields are filled out, they can be sent as "blanks" to the action app. We can slow down the zap for you so it runs less frequently but has a better chance of being fully transcribed. Just contact us.
This is due to the way you've provisioned your API Keys on the Nutshell side. When creating your API Key, you'll need to select the "API Access + User Impersonation" option in order to test triggers in Zapier properly: