“We will explain in this blog how to enable Flex Cards.
Step1: Open OmniStudio in App Manager
Step2: As you unfold the Flex Card, a thoughtful message emerges, gently reminding you that the creation of this card awaits resolution of the associated warning.
To fix this warning, go to the warning tab and find two links. Click on each link, and it will take you to Remote Site Settings. Before that, go to setup.
You need to set up the remote site before making a flex card; otherwise, there might be an error when creating the flex card.