i've been experience this before..whenever i topup rm10, it can only lasts for a few days although i didnt make many call/sms..
at first i didnt bother with it since im not tracking how many call/sms i did but after a few topups, it comes to my attention that something unusual is happening..but the thing is i didnt receive any sms that could indicate what is sucking my credit..thats even worst

after i realizing that, i goes to celcom branch near klcc, and asked them why and so on..the exec said i've 3 subscriptions..damn..i'm really2 sure i didnt subscribe to any of this sms..

i did ask the exec, and she replied 'owh perhaps u accidentally subscribe to the content'..mang the way she replied and her face shows that this is something usual and she ready to spit out the answer to tackle customer questions..

so i managed to stop all subscriptions by sending stop all message and since then i've no weird sms sucking my credits..but how did they manage to subscribe me without my concern..thats something to ponder..