Visual Builder for Contact Form 7compatibility issues
Contact Form 7 – PayPal Add-On Pro and Visual Builder for Contact Form 7 do not work correctly together.
Basically Contact Form 7 provides instructions for how other plugins can integrate with it and the date picker plugin does not follow these instructions.
However there is an easy solution. If you temporally disabled the Visual Builder for Contact Form 7 plugin you can modify the elements on the PayPal tab of your form. When you are done simply save the forms like normal then reactivate the Visual Builder for Contact Form 7 plugin.