How to turn off the flow of the secondary card? I want to limit the flow of the secondary card

1. Take Apple 1 1 as an example, go to the iPhone home page and click Settings, as shown below:

2. Click cellular network in the setting interface, as shown in the following figure:

3. Click Cellular Data to enter the cellular network interface, as shown in the following figure:

4. Switch the cellular data to the master card and turn off the automatic data switching at the same time, as shown in the following figure:

5. Go back and click on your secondary card to enter, as shown in the figure below:

6. Enter the secondary card and click Voice and Data, as shown in the figure below:

7. Set the voice data to 4G, and turn off volte, so that the data flow of the secondary card will not be enabled for surfing the Internet or making phone calls, as shown in the following figure: