Hello @AmandaT784. I apologize that your contact is having trouble receiving the confirmation email. I do see that your account does not have the Confirmed Opt-In setting activated. This does need to be turned on in order for the confirmation email to be sent to contacts who want to resubscribe. Here are the steps needed to do this.
Once you have activated Confirmed Opt-In, you aren't able to resend the email, however you can send the contact a link to your sign up form. Here is how to find the link for your sign up form. After they enter their information, they should then receive the confirmation email.