iStock/Thinkstock(CHICAGO) — During the peak of Black Friday shopping madness, a glitch in Macy’s credit card system caused registers at the retailer’s stores to stop working.

At the Macy’s in downtown Chicago, one salesclerk had to enter credit card numbers manually. Most purchases, appeared to go smoothly, however, and lines at the registers did not appear to have more than five to six people queued.

“It is taking longer than usual to process some credit and gift cards in our stores, but we have added additional associates to the floor [who] are working to resolve the issue as quickly as possible,” said Andrea Schwartz, vice president of media relations for Macy’s.

The cause of the issue was not immediately clear and it was not known how long the problem would last.

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