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 completed the recommendation but not yet submitted. Please have them login to their account, click the “FINISHED?” section to the left side of the page to complete the recommendation. Then they will be able to submit. 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.