The issue affected around 4,500 customers and calls made between 3 a.m. and 12:20 p.m., including some emergency calls. Dapto is about 60 miles south of Sydney.
Optus suffered another outage that disrupted emergency calls, just as a delegation from parent company Singapore Telecommunications visits Australia this week to meet Communications Minister Anika Wells over fallout from earlier disruptions.
Optus continues to investigate the cause of a now-restored issue involving a mobile phone tower site in the Dapto area of New South Wales on Saturday, a spokesperson said.
