How to switch data traffic between two mobile phone cards?

You can refer to the switching mode of vivo mobile phone: enter settings-dual card and mobile network-open intelligent switching data card. After starting, the data network will automatically switch to the secondary card if any of the following conditions are met:

1. Using mobile phone cards of two different operators, when the network of the primary card (default data card) is poor and the network of the secondary card is good, the data network will temporarily switch to the secondary card, and after the network of the primary card is restored, the data network will automatically switch to the primary card;

2. When the secondary card is in the VoLTE network and the secondary card is a cartoon, the data network will temporarily switch to the secondary card. After the call, the data network will automatically switch to the main card (default data card).