There are a few things you can do if your defaults are not sourcing into your forms. First, ensure that you have saved and activated your defaults prior to closing your Preferences by checking the box entitled 'Activate Defaults' from within your Defaults page. If you did close the page prior to saving or activating the defaults, try removing and adding the information, saving, and activating the defaults.
Please note that there is a hierarchy for which information will take precedence within WebForms. For example, if information is sent on a Purchase Order that will source onto an Advanced Ship Notice, this will take precedence over your defaults. You can work around this functionality by utilizing 'Setup Lookups'
As always, please log an issue with Customer Operations if you continue to experience issues and one of our analysts can review the specific situation with you to find a solution best fitting your needs.