Telstra has said its services are improving, following a nationwide outage on Monday morning.
"Our 4G voice and data traffic volume is improving nationally after we bypassed hardware that had been preventing some customers from accessing the 4G mobile network. 3G voice and data volumes are also improving," the telco said.
"We're very sorry for the interruption to services."
According to complaints on Monday morning made to Telstra's Twitter account, users from all over Australia had fallen victim to the outage.
"The issue is impacting some 4G mobile voice and data services nationally, which is also causing congestion for 3G services. We're working to resolve the issue and are investigating the root cause," Telstra said on Twitter.
NSW Police warned the outage may hit Triple Zero services, and advised that people use another carrier while the outage exists. Telstra however said calls to 000 will connect over other carriers.
In May alone, the dominant Australian telco has suffered a pair of outages.
The first impacted 4G voice calls, which Telstra put down to "upgrades to mobile traffic control equipment in Telstra's Exhibition Street exchange in Melbourne".
The second took out Triple Zero and mobile voice services, when a fibre link between Orange and Bowral suffered fire damage consistent with a lightning strike.
Australia's incumbent telecommunications provider had similarly suffered a 4G outage in September last year, at the time saying it "very quickly" repaired the issue.
It last year also experienced an outage across fixed-line and mobile services due to a fire at its Chatswood exchange, which caused SMS messages to be delivered to the wrong people, along with an enterprise voice and data outage caused by faulty hardware, which both occurred during February.
Telstra last week revealed its earnings for the full year to be at the bottom end of its AU$10.1 billion to AU$10.6 billion guidance range.
Updated at 12.25pm AEST, May 21, 2018
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