As far as I know these are MTNs rules on deactivating their sim cards:
When a prepaid sim has not made a chargeable call for 30 days, the following SMS reminder message is sent to the
“Yello! To keep your cellphone number active, you need to make a call, send an SMS or MMS or load an airtime voucher every 90 days with MTN Access4Life.”
When a prepaid sim has not made a chargeable call for 85 days, the following SMS reminder message is sent to the customer:
“Hello. As you have not made a chargeable call on MTN for 90 days you will be deactivated from MTN’s Pay As You Go system in 5 days. For more info, call 083173.”
The Access4Life Rule Table depicts which prepaid activity will count towards Access4Life rules.
If the customer has not complied with one of the applicable Access4Life rules in a 90 day period, the customer shall be deactivated after 97 days.
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