The Nokia 2720 is a dual-band Global Systems for Mobile Communications (GSM) cellular telephone that was originally released in May 2009. In the United Kingdom, the phone is sold by the cellular service provider Tesco Mobile. Tesco generally sells the Nokia 2720 with a carrier lock that prevents using the phone with another cellular service provider's Subscriber Identity Module (SIM) card. If you want to use your phone on a non-Tesco network, you must unlock your Nokia 2720.
Call Tesco customer service and ask for the unlock code for your Nokia 2720. Tesco will generally provide you with the unlock code for your mobile phone free of charge if you have an active account in good standing. Alternatively, purchase the unlock code from a company that specialises in selling unlock codes for cellular telephones. Write down the unlock code.
Slide the back cover off the Nokia 2720 and remove the battery from the phone. Under the battery compartment, you will find the Tesco SIM card. Remove the SIM card and replace the battery and the phone's back cover. Power on the Nokia 2720.
Type "#pw+CODE+1#" using the Nokia 2720 keypad. Replace "CODE" in the sequence with the unlock code you wrote down in Step 1. The phone will display the message "SIM Restriction Off." Your phone is unlocked, and you can now use it with a non-Tesco SIM card.
To type the letter "P," press the "" key three times. To type the letter "W," press the "" key four times. To type the "+" symbol, press the "*" key two times.