Please make sure the plugin is activated and there are no other Gravity Forms plugins interfering. I've tested my plugin with all the official Gravity Forms payment addons. But there are other third party plugins that don't follow the Gravity Forms API rules and break the flow. Try disabling any third party Gravity Forms plugins and see if the echeck fields reappear. If so, then enable the other plugins one by one until you find the plugin that breaks it. If not, contact me via email and I will help you figure it out or refund your money.