Currently im using postpaid u28.because i thot naah i dont need voice call n will call ppl using viber, line etc...but everymonth the bill will be like rm40-50 since keep calling ppl who don't have all that apps.. thus now i feel sigh, i shoud just take prepaid u28 instead of postpaid..
So can i change my postpaid to prepaid..i knw it will be just 500mb..
Let say i succeed to change my postpaid 28 to prepaid u28,in future can i change it back to postpaid(when i finished my studies hehe)?
Thanks

Objective: to maintain my mobile number.

Info: currently i am a subline under my mom, using maxis, RM30 a month. no internet. I want to maintain my number, as i'm only back in malaysia during weekends. If i want internet, i can subscribe to the 1 day RM5 internet plan.
What is the cheapest option maintain my number? I dont mind porting to other telcos.