After updating to Caldera Forms 1.7, if your server does not meet the minimum requirements, you may see the message “Your version of WordPress or PHP is incompatible with Caldera Forms” where your form previously loaded. This message will show in place of a form if you attempt to use Caldera Forms 1.7 or later with an incompatible version of WordPress or PHP.
Here is the relevant documentation to resolve this issue:
PHP Version Announcement and What It Means for Caldera Forms Users