Standard Bank South Africa CEO Lungisa Fuzile has apologised profusely for the bank’s downtime at the weekend, which prevented clients from transacting for an extended period — just the latest in a series of incidents.

Fuzile, speaking during an online media briefing on Tuesday, said the downtime, which lasted for about six hours through the busy Saturday morning shopping period, was caused by a failure with a “generic switch” used for inbound and outbound transactions, which required the bank’s engineers to rebuild the architecture from the ground up in a matter of hours.

“We want to express our heartfelt and most sincere apology for the inconvenience caused by these events,” said Fuzile. Standard Bank has had several digital outages in recent months, but the bank said the latest incident is not related to previous problems, which it blamed on a “software bug” that has now been fixed.

The bank assured its customers that it is working hard to bring stability to its systems, including cutting many of its IT systems across to the Microsoft Azure and Amazon Web Services cloud platforms.

Fuzile said Saturday’s outage meant Standard Bank systems, including ATMs and point-of-sale devices, became “almost wholly inaccessible” to most of its clients.

Khomotso Molabe, chief engineering officer at Standard Bank South Africa, said the failure of the switching platform started at about 7.30am on Saturday. By 9am, the problem has become so severe that most of the bank’s customers were not able to transact. Business clients were also impacted because they weren’t able to receive payments.

“It was the first time we have seen this type of failure on this component, at least in the last four years,” Molabe said. When it failed, the bank’s engineers worked quickly to determine the problem. They realised they’d need to build a new switching environment, which was done in a matter of hours. Services were restored in the early afternoon on Saturday.