TELSTRA says the latest outage has been fixed but some customers say they still can’t use the network.

In a statement, Telstra said Tuesday’s outage was caused by a “card failure in a media gateway in Victoria which meant certain calls could temporarily not get through”.

The telco has also said it will be conducting a major review of the three recent outages.

“While small, we appreciate the impact this outage had on the customers affected, and we apologise to them,” the statement said.

“While we have the leading network in Australia, like many of our global peers there will always be issues that arise in such a large and complex technology environment.”

A Telstra spokesman told news.com.au the interruptions lasted for about an hour.

“(It) impacted less than three per cent of our mobile customers, mostly in Victoria and Tasmania with intermittent issues in other states,” he said.

The company earlier said the problems that caused the disruption nationwide had been fixed.

But some customers in Queensland, South Australia, Western Australia and Victoria complained they were still unable to connect to the network hours after Telstra said the issue had been resolved.

On Twitter, Telstra was advising customers that it was “investigating some residual issues for a small number of customers”.

@Telstra really? Still outages in the CBD and have missed several phone calls! Come on guys, be honest! — Simon Torok (@simontgeek) March 22, 2016

@CharisChang2 DEFINATELY NOT FIXED!!!!!!!!!!!!!! I'm in the Sunshine Coast. — Lisa Burgess (@rspllb020770) March 22, 2016

@CharisChang2 @newscomauHQ I'm in Perth and still no service here either — Ian Skeggs-Grant (@ChopperSG) March 22, 2016

@CharisChang2 they have not resolved nothing still can't make or receive calls — Milsyg78 (@Milsyg78) March 22, 2016

EARLIER

Twitter was flooded with complaints from people suggesting their mobile service was not working. The latest Telstra outage was the third one in two months.

A Telstra spokesman confirmed that customers were reporting difficulty making voice calls on fixed and mobile networks.

“We are investigating as a priority,” he told news.com.au. Tweets from the telco’s official account suggested the outages appeared to be mainly in Victoria and Tasmania. However, users in Brisbane, Perth, Sydney, Adelaide and Hobart have reported being affected.

As complaints started to roll in, Telstra’s official Twitter account advised one person to try turning their mobile phone on and off again.

@tminear Have you had any success Tom turning the handset off and back on again? - Jo — Telstra (@Telstra) March 22, 2016

Can confirm #TelstraOutage here in Brisbane. Trying to call between two @Telstra mobiles: Long silence then call failed. — Nikolai Hampton (@NikolaiHampton) March 22, 2016

Definately in Melbourne. Jusy been advised could be while. Three strikes Telstra...@Telstra https://t.co/lr3TOTZrxw — Scott O'Neill (@ScottONeill2) March 22, 2016

.@Telstra another mobile outage?? This is getting silly. You have just lost me as a customer when my contract comes up. — Justin Mansfield (@joininthechorus) March 22, 2016

Anyone having issues making calls on @Telstra I cannot get through to any mobiles and need to make sales, help! — trevorvas (@trevorpvas) March 22, 2016

Perth and Melbourne affected by Telstra outage. Anyone else? — Ahron Young (@AhronYoung) March 22, 2016

It is the second outage to hit the Telco in the space of four days, and the third incident in two months.

Last Thursday, millions of Telstra customers across Australia were unable to access phone and internet after a large number of services to be disconnected at the same time, causing extreme congestion.

The outage caused Telstra CEO Andrew Penn to issue a grovelling apology, saying he accepted full responsibility for the problem and offered customers another data free day on April 3.

Thousands took to social media after being unable to access their services around 6pm last Thursday.

While services were restored within four hours, some customers complained of ongoing problems into the next day.

At the same time, other Telstra users complained of poor internet speeds, broken landlines and failure to access various websites with the finger being pointed straight at the Telco.

A spokesman for Telstra told news.com.au last week that it appeared there was a routing issue between Telstra and Amazon Web Services.

It followed a huge outage in February, that Telstra blamed on an “embarrassing” error made by a worker.

At the time IT operations consultant Sam Newman of ThoughtWorks, told news.com.au it was surprising that Telstra chief operations officer Kate McKenzie would blame one person for the outage.

“It’s about the system you create, it’s not about individuals,” he said.