How to top up smart prepaid sim card

Buy a smart call and text card, Lightly scratch off the protective ink on the card to reveal the 14-digit PIN. On your smartphone press 1510+(14-digit PIN on the smart call and text card) and press send.

How to know my sim card number on LG K4 LTE

Find About phone on General Settings, look for status where you can find your phone number, IMEI and IMEI SV.