With this option, you can limit the number of form entries you receive and restrict multiple form entries from the same respondent or the same IP. Once the entry limit is reached, the form's link will be disabled.
To do this,

1. In your form builder, navigate to the Settings tab.
   
2. Under Form, click Form Span.
   
3. Under Restrict by Submission, you can choose from the following options:
   
   

• Restrict Number of Submissions: Choose Yes to obtain only a certain number of entries through your form. You can restrict your users from accessing your form by setting the maximum number of entries it can accept. Enter the maximum number of entries allowed and a deactivation message that will be displayed to the respondents once the limit is reached.
• Restrict to One submission per IP: Choose Yes to ensure that you do not get multiple responses from the same system (IP address).  When a user accesses your form a second time from the same public IP address, the form does not load.
• Restrict to One Submission per Respondent: Choose Yes to obtain only a single form submission from your respondents. This option works only within your Zoho Forms organization when logged in users submit entries via privately shared forms.