If you forget to renew your domain with Hostinger before its expiration date, your domain will go into a grace period, during which you can still renew it without incurring any additional fees. If the grace period passes, there will be an additional redemption period during which you can still reclaim your domain but with a redemption fee. However, if the redemption period elapses, your domain will be released back into the available domains for others to register. It's essential to keep your domain registration up to date to avoid losing ownership.