Vodafone UK blamed changes to its customer care systems for a steep rise in the number of consumer complaints made about the operator to regulator Ofcom in the final three months of 2015.
The UK operator told BBC News it has made 350 changes to its IT systems in a bid to correct problems that resulted in the company becoming the country's most-complained about service provider in the October to December quarter.
Ofcom announced in late March that the number of complaints regarding Vodafone UK reached 32 per 100,000 customers in the final quarter of 2015, well above the industry average of 10 complaints per 100,000 customers. In a report, the UK media and telecoms regulator stated that the bulk of complaints against Vodafone UK related to "issues about billing, pricing and charges, complaints handling, and fault, service or provision issues."
A Vodafone UK spokesperson told the BBC that customer service was affected by changes to its billing systems, and amendments to its call centre processes along with the appointment of new customer care staff.
The operator faced further pressure regarding its customer service in April when consumer champion Which? announced that Vodafone UK and EE fell short in an annual mobile satisfaction survey. The operators ranked in a joint 10th place in the survey, with an overall score of 49 per cent.
The BBC noted that Vodafone UK is still preparing a response to a separate Ofcom probe regarding pay-as-you-go (PAYG) services.
Ofcom in April announced that an investigation of Vodafone UK's PAYG billing practices covering the period from May 2011 to September 2015 appeared to show that the operator breached consumer protection laws. While the regulator has the ability to fine Vodafone UK up to 10 per cent of its turnover as a financial penalty, the Financial Times reported at the time that such a hefty fine was unlikely.
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