Whenever a domain expires it usually enters Grace period, which is indicated on the Domains dashboard. Hovering over this status will show how long will the domain stay in the Grace period before it enters Redemption:
To renew such a domain, all you need to do is click on the Renew now button.
Once a domain passes the Grace period (usually lasts around 30 days) it will enter Redemption:
In order to renew your domain from Redemption, you will need to contact our Customer Success team and pay an additional fee depending on the TLD.