Thousands of users in the United States complained on Friday that the American Express card system was not working.
According to Downdetector's map of reported problems, the highest number of complaints about the service came from US' northeast, particularly from New York City, Los Angeles and Atlanta.
Approximately half an hour later, the number of reported problems declined in Los Angeles and Atlanta, but rose sharply in Dallas, Texas, Chicago, Illinois and Minneapolis, Minnesota, according to the live map data.
Most of those experiencing problems said that they were unable to use credit cards, which accounted for about 76% of complaints.
The second most common problem was customer support, which reportedly did not work for about 18% of users.
Interestingly, issues were also reported by clients of other major payment systems, such as Visa and MasterCard, but they were not of such a widespread nature, as with American Express.