Sydney law firm PiperAlderman is seeking out disgruntled Vodafone customers to form a class action lawsuit over dropped calls, reception issues and poor data performance that have left customers fuming.

The Australian Competition and Consumer Commission (ACCC) has already said it is investigating the matter.

Vodafone initially blamed software bugs and argued that there were no serious problems with its network.

Its furious customers then took to social media and sites like Vodafail.com, forcing the telco to admit to some remaining issues. But customers calling its customer care line have been placed on hold for hours on end and then forced to fill out long, laborious forms.

Some customers who complained the loudest and contacted the Telecommunications Industry Ombudsman (TIO) have been able to get out of their contracts and received compensation but others have given up long before this stage.

"Calls dropping out, reception issues, poor data performance – this is not what Vodafone customers signed up for," wrote PiperAlderman in a notice on its website.

"Vodafone, however, has continued to charge customers on its mobile plans, without providing the service it promised."

The law firm said customers who signed up with Vodafone over the last three years may be entitled to compensation "if they were misled into signing contracts or if Vodafone did not live up to its end of the bargain".

It said it was investigating a class action against Vodafone to recover losses suffered by its customers over the last three years, plus interest.

"There will be nothing to pay unless you successfully recover compensation," the firm wrote.

Many Vodafone customers have said the constant call dropouts and reception issues have meant they have been unable to properly operate their businesses. Others have said they have been unable to call emergency services after being involved in an accident.

A litany of Vodafone customer horror stories can be found on the Vodafail.com website.

The owner of the site, Adam Brimo, has had legal threats from the telco and had the site's logo removed from Facebook due to "copyright infringement" – a move he believes was sparked by a complaint from Vodafone.

Brimo has analysed contributions to Vodafail.com and their associated IP addresses and believes Vodafone dealers and staff members are taking to the site to defend the telco without identifying themselves.

"They have been quite aggressive, the general tone is that it's the customer's fault and that all of our complaints are about tiny problems," said Brimo.

"Some have also said that if we don't like it, we should just leave, of course leaving Vodafone is what everyone is really trying to do."

Vodafone says there is no concrete evidence the posts came from its staffers.

Brimo, who was recently let out of his Vodafone contract, has now implemented a coverage map on Vodafail.com which, based on user reports, identifies problem areas on the telco's network.

On Tuesday last week, after organisations like the Australian Communications Consumer Action Network (ACCAN) chastised the telco for failing to inform customers of its issues, Vodafone CEO Nigel Dews published an apology on Vodafone's website.

The apology provided no new information on when issues may be fixed but referenced a network upgrade which is not due to be completed until some time next year.

On the prospect of a class action, Dews said in a statement that the most important thing the telco could do was to focus on improving its network and customer experience.

"We are also in regular contact with the ACCC and other consumer groups to advise them of what we are doing to improve network performance and services to our customers, and we are keeping our customers across changes through our website," he said.

"Our network performance is improving and we are confident that things will get better as we continue to roll out extra capacity across out [sic] network."

The same statement was sent out to Vodafone staff members but it contained an additional line not sent to this website. "It's obviously very disappointing to hear that a legal firm is using this to drum up business," Dews wrote in the email, seen by this website.

Despite the immense issues faced by its existing customers, Vodafone continues to spend millions on advertising for new customers, including as a primary sponsor of the cricket.