I had a contract Sim only with Tesco mobile. I was told that I could cancel the contract after 12 months. After 3 months I stop using it. Religiously I paid every month without using it. After 18 months I cancelled the direct debit as advised when I took the contract. Without any notification I have received a letter from a debt collection agency because Tesco mobile failed to collect £20. What a joke, they don't put the prices up but they stich you up.