Shanghai Chang Go Corporate Services Co Ltd, a prepaid cards issuer, was operating against regulation which resulted in liquidity problem and settlement failure with merchants, a notice from People's Bank of China Shanghai headquarters said Tuesday evening.

It added that cardholders were not able to use the prepaid cards as the issuer was facing liquidity problem.

The cards issued by Chang Go have been rejected since December in many department stores and supermarkets, said cardholders.

Chang Go holds a third-party payment license issued by the People's Bank of China, and it has approval to issue the cards in Shanghai and the provinces of Jiangsu, Zhejiang, Anhui and Shandong, according to the official website of the company.

The website also said these cards are valid in more than 20,000 stores and supermarkets in the Yangtze River Delta.

The company has posted notices on its offices in Shanghai and Ningbo saying it has been working on restoring the cards functions.

China Daily called the hotlines shown on the company's official website, but nobody answered the phone on Wednesday.