Major online shopping platforms are rushing to address the shortage of delivery staff due to the increasing number of residential complexes in Shanghai under quarantine.Shoppers may have to wait one or two days after placing online orders for deliveries depending on regional supply situations.Online grocery and fresh food sites including Meituan Maicai, Freshippo, Dada and Dingdong Maicai that usually promise one- or two-hour delivery time have delayed their schedule citing a temporary shortage of workers.