Why can the primary card receive the Migu video message opened by the secondary card?

The secondary card is in arrears When the secondary card is in arrears, and then the primary card needs to make up the arrears, you can receive the message that the secondary card cannot receive it. The primary and secondary cards are only for packages and fees, and they are used independently. The primary card can't view the messages sent and received by the secondary card. The function of the main card is more and more perfect than that of the auxiliary card, and different versions are different.