A 7-Eleven hack in Japan has seen some 900 mobile-payment account holders lose money. 

The consumers collectively lost ¥55 million (US$510,000) following the cyberattack, which gave unauthorised access to their user accounts and revealed their credit or debit card details. The service was launched less than a week earlier and rolled out in more than 20,000 stores nationwide before the hack was committed, which began within a day of going online.

The company has promised to compensate the affected users, according to Seven Pay Co.’s president Tsuyoshi Kobayashi. New user registrations and funds-adding features to the service have already been suspended.

Other Japanese retailers recently affected by hacking operations include Uniqlo and Aeon.