If a SIM card has used the included volume of 500 MB before the activation period of 10 years is up, it remains activated for a maximum of 18 months from that point on. During this time, the customer has the option to purchase another data volume of 500 MB for another 15 USD. If the customer does not book additional data within these 18 months, the SIM card is automatically deactivated by the system when the eighteenth month is up.