You must have purchased prepaid SIM Card credit and now you need to follow this instruction if you are having trouble to recharge your credit. This is credit recharge instruction for prepaid SIM card (7 Mobile)
OPTION A [How to Recharge Prepaid Credit website]
(1) Insert Prepaid phone number to be charged then press the button on the right side. (Send Authentification Number)
(2) Check your cell phone and Enter the digits of authentification number
(3) Insert Prepaid recharge code(11 digits) then press the button for recharging
(4) Click the red button to recharge
(5) Press #114 then press the call button or check your increased balance online (https://www.sk7mobile.com/cust/pre/myService.do)
Are you having trouble with loading page in English? Please visit here
(https://www.sk7mobile.com/cust/pre/chargeMain.do) and select English then click “PPS cards recharge”
OPTION B [Credit recharge using ARS]
This option often causing technical errors. Please consider to recharge code using option A.
(1) Press 114 then press “call” button. If you are using another phone to recharge then you can call 1599-0999 or 080-899-0999.
(2) Enter your mobile phone number followed by the (*) key
(3) Please enter the 11 digit number (Recharge CODE) that Kimchi Mobile provided.