Follow these steps to limit the number of responses to a form.
1. Navigate to the Settings tab in the Form v2 page part and select Response Limits.
2. Make sure Limited Responses is turned on.
3. Once turned on, you can set the number of allowed responses, along with a custom message that will appear once the limit has been reached.
4. By turning on Response Count Message, users will see the number of remaining allowed responses.
5. Be sure to Save Settings when you are done.