MCI sim cards’ sudden deactivation

It appears it is not confined to any specific code and despite previous notion that this occurred with old sim cards, it even happened to codes 5 and 6 which are relatively new.
The company has so far given no logical explanation on the matter and most subscribers have resigned to paying for sim card reactivation.
The operator has around 35 million subscribers in the country of whom over 16 million are postpaid sim card subscribers.
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