SINGAPORE – Some customers were still unable to transact on DBS’ website and mobile app for the third day on Thursday morning (Nov 25) even though the bank said services were returning to normal late last night (Nov 24).

In a Facebook post at 10:35pm on Wednesday (Nov 24), DBS said: “Please be informed that our digital banking services are returning to normal. We are monitoring the situation closely to ensure all services run smoothly. Thank you for your patience.”

Even though customers could log in to its digibank online platforms on Thursday morning, many still said they could not transact or view past transactions.

“I can log in now. But I cannot view my credit card transactions. Every click to card transaction is quickly refreshed back to main dashboard summary page,” said Facebook user Jack Tan in a comment at about 7.40am on DBS’ post.

Another Facebook user, Ms Allison Teo, commented at about 8am: “Able to login, but it hangs and not able to click on any icon.

Reacting to the bank’s worst outage in more than a decade, the Monetary Authority of Singapore (MAS) said on Wednesday evening that it would consider taking “supervisory action”.

“This is a serious disruption and MAS expects DBS to conduct a thorough investigation to identify the root causes and implement the necessary remedial measures,” said MAS assistant managing director of banking and insurance Marcus Lim.

“MAS will consider appropriate supervisory actions following the investigation. MAS expects all financial institutions to have systems and processes to ensure the consistent availability of financial services to their customers,” he said.

Under the central bank’s regulations, financial institutions must ensure that the total unscheduled downtime for critical systems affecting services for customers does not exceed four hours within any 12-month period.

The app was still inaccessible at 5pm on Nov 24 (left). At 10.35pm, DBS said its digital banking services were “returning to normal”.ST PHOTOS: BENJAMIN SEETOR

Banks must also inform MAS of any incidents affecting critical systems within an hour.

In a Facebook video post on Wednesday, DBS country manager for Singapore Shee Tse Koon apologised to affected customers for causing them inconvenience and blamed faulty access control servers for the outage. He did not elaborate on details of the server fault.

Access control servers are part of a bank’s security system. They handle both log-in and payment verification using means such as biometrics, authentication tokens and one-time passwords.

The disruption, which was first reported at around 10am on Tuesday, is the worst DBS has seen since 2010, when a major systems failure took down all consumer and business banking services at DBS. Customers were unable to withdraw cash from ATMs or make point-of-sale payments for about seven hours.