Changing someones status on the Global opt in setting from "no" back to "yes"

Summary

Looking for support to a question I couldnt find on the forum about re-adding a customer to the global opt in list when they unsubscribed by accident

Content

hi everyone

We have a customer who queried why they were not receiving mailings from us. It turns out they had clicked an unsubscribe link on one of our previous emails and they have requested for us to take them off the suppression list in order for them to receive mailings again.

Is there a process whereby we can reset the clients status so that their global opt in setting allows us to send maillngs to them again?