The 'Checklist' is updated automatically and instantly when the recommendation is completed online. If your 'Checklist' does not say it is submitted, then the recommender has not submitted online.
They may have filled the recommendation but not yet submitted. Please have them login to their account, click the “Review in Order to Submit” section to the left side of the page to submit the recommendation. In addition, if they sent the recommendation without using the online system, your 'Checklist' will not update with this information and you should contact the school directly for its submission status.