To avoid spambots, you need to protect reservations by applying a form with a captcha. This requires at least one captcha plugin to be installed, active and properly configured. To do this:

1. Go to the component's "Reservation settings" tab.
2. Select your captcha plugin in the "Captcha" form field. In our case, it is ReCaptcha.
3. Save configuration.
4. The result now looks like this (image #2). The form is now protected with a captcha.