Cape Town - ABSA bank's services were offline for a few hours on Saturday, preventing clients from making payments or drawing money.
Clients were upset that they were not warned in advance of the downtime, which happened from 12:52, according to website DownDetector.
DownDetector tracks reports of apps and services not working.
According to DownDetector services impacted include mobile banking, online banking and the website.
ABSA responded on Twitter by 14:00, indicating that it was experiencing "technical difficulties" and that it had teams working to resolve the problem.
Shortly after the bank tweeted that services were working as normal.
But a user, @TS11110 tweeted around 17:00 that the banking app was still not working.
More users expressed their frustrations on Twitter, as the downtime had affected their weekend plans.
Some clients complained that they could not buy food.
Another user @asijoli2018 was also stranded at a petrol station and had to rely on someone else to pay so that he could leave.
ABSA has not yet responded to Fin24's queries about the extent of the outage and which services were affected.
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