Mobile phone customers are facing contract exit charges of up to £800, a charity has warned.
The Citizens Advice Bureau says it has dealt with 21,500 complaints relating to mobile phones in the last year, of which 8,800 (39%) have been calls relating to faulty handsets, This is Money reports.
The charity provides the public with the advice and information needed to help them solve their own problems.
They have said that an overhaul of mobile phone contract rules is needed to stop customers being taken advantage of.
Chief Executive of Citizen Advice, Gillian Guy, said: "With mobile phones now an essential utility, longer contracts can be a good thing for consumers but only if their rights are protected when they sign up."
Other examples of issues customers faced include lack of 3G and 4G coverage, despite it being promised.
In some cases this has resulted in customers being forced to carry on paying their contracts fully, or pay the remainders which can total as much as £800, Sky News reports.
Gillian Guy added: "Consumers should only be paying for the service they receive. For consumers to be guaranteed a good deal from their mobile phone providers, clear minimum standards of service and better contract exit rights are needed."
Sky also reported that many customers are confused about who they should be reporting their mobile phone issues to and whether they should contact the retailer or the network.
Citizens Advice have also called for a cap to be introduced in relation to mobile phone bills that are run up on stolen phones.
The charity found that as much as £14,000 was lost by consumers since March last year, which is when the government initially said the cap would be in place.
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