You can resend a request to any recommender who has not responded to your initial request. Locate your application dashboard and click on "Program Materials", then click on "Business Administration (MBA)", and then click on "Recommendations". From this screen, you can see the list of your recommenders and choose an action for each. Click on the pencil icon located to the right of the recommender's name, scroll down to the bottom of the page, and click on "Resend This Recommendation Request".