Usually in a mobile phone contract, the service provider charge you for the cost of the handset as well as for the network services for a specific period of time, that's the duration of your contract. Once your contract term is completed, the service providers drops your monthly payments to network services charges only. If the service provider has been wrongly charging you the contract charges even after its expiry, then you are due refund for the overpayments you have made.
You need to make a formal written complaint via your service provider internal complaint procedure, asking them to refund the overpayments .
If the service provider fails to resolve the issue, you can escalate the matter to the services ombudsman, once you have the deadlock letter from your service provider.
you can make a complaint to services ombudsman online using the below weblink-
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