If you are using a celcom prepaid, you can subscribe to daily, weekly or monthly broadband internet by dialing *118#. If you want to unsubscribe any internet subscription above, simply type STOP (capital letter) and send to 28882.
send to 28882
This method valid for any prepaid users. Before this, celcom will ask users either to continue or stop their internet subscription before the subscription period end. However now your subscription renewal is automatic and you need to stop the subscription manually otherwise it will continue to subscribe until your are out of credits.
You do not have to worry because celcom will notify you about the automatic renewal with SMS. If you get an error after sending STOP to 28882, just try later and they will notify you with an SMS saying your are no longer subscribed to the any internet plan.