The only way to remove an individual your company-wide opt out list is to have them opt 'back in' to text messages from your organization.
To do so, have them text initiate a text message to any of your text-enabled numbers with the keyword: OPTIN.
- To view your opt-in or opt-out list any at time, log into the Admin. Portal and click on the Compliance Tab > Reports. From the drop down, select either the "Opt-In" or "Opt-Out Report".
Opt-in notifications
Once opted-in, the recipient will receive an automated reply confirming their opt-in status: "Thanks for signing up to receive SMS messages! Msg & data rates may apply. Reply HELP for help, STOP to opt out."