How to unlock TCL LX / TCL A502DL using OTSMART ?

1. Download from the support area A502DL-2AKFUS7_UNLOCK_FIRMWARE.osp

2. Start latest version of OTSmart and select the model from the models list

3. Choose Write Firmware from the Operations Box and choose the file you previously downloaded

4. Press Connect and attach the phone powered off (no buttons pressed) to the usb cable

5. Once the flashing completes start the phone , configure it and go System->Network & Internet -> Cellular Network -> Allow 2G service and enable it ! Also do note that  this phone support a limited set of bands so be sure that your operator supports it.