If the main card and the secondary card use the same account, then the secondary card can also pay the main card; However, if the main card and the secondary card are charged separately, then the secondary card cannot pay for the main card, and under normal circumstances, you can call the operator's customer service for inquiries.
The main card and the secondary card must be closed, and the main card and the secondary card shall be paid in a unified account format. Any mobile phone number in the main card rights and secondary cards can be used as a unified account payment