It's important that you respect the wishes of those who have opted out of your survey. Use the Manage Opt Outs page to do so.
Go to Surveys & Data Collection | Survey Hub | <desired_survey> | Manage. On the Manage Survey page, click Manage Opt-Outs:
The opt-out list contains the email addresses of people who have opted out of future emails sent about a specific survey, from your user account, or from your entire company.
Email addresses listed in the table will not be sent invitations to take the survey. Use the opt-out list to:
1. Manually add opt-outs.
2. Delete opt-outs.
Note: Accessing the opt out list allows you to remove addresses from the list as long as they opted out from the specific survey or your account. Only a system administrator can remove an email address from the list if the respondent opted out from the entire company.