Your store is in preview mode
While your store's theme is in preview mode, Fundlify campaign widget may not show, you need to exit the preview mode to display the widget.
HTML tags in Campaign Messages
If you've added any HTML tags in message fields in settings > language, Fundlify widget may not show.
The product inventory level is below zero (-1)
The inventory level of the product you've added to your campaign is below zero (-1)