Department store operator Macy's Inc said that processing of payments with some credit and gift cards was taking longer than usual in its stores on Black Friday, the traditional start of the key holiday shopping season.
Customers took to Twitter on Friday to complain about credit card machines not working in stores and online accounts not working.
"We have added additional associates to the floor (and) are working to resolve the issue as quickly as possible," Macy's spokeswoman Radina Russell said in an emailed statement.
A Macy's customer service employee contacted by phone said she was unable to provide assistance due to technical issues.
Macy's chief executive, Jeff Gennette, told CNBC on Friday that the retailer was better off this year than last, had robust online demand and was in a good place for holiday promotions. (Reporting by Richa Naidu; Editing by Leslie Adler)