What if Apple 12 doesn't switch the primary and secondary cards when sending text messages?

Apple sends text messages to switch between primary and secondary cards, taking iPhone XR as an example. The specific steps are as follows:

1, open your mobile home page, and click Info to enter, as shown in the figure below.

2. Enter the information interface and click New, as shown in the figure below.

3. Enter the new interface and click the recipient, as shown in the figure below.

4. Enter the recipient number or add an address book, as shown in the figure below.

5. After adding the recipient, the default mobile phone card name will appear. Click on the mobile phone card, as shown in the figure below.

6. The option of two cards appears, and switch to the card you want to use, as shown in the figure below.

7. If the handover is successful, enter a short message and click Send, as shown in the figure below.

Set the default number:

Usually, we call the card that needs to open mobile data as "main card (main number)", while another card that can only be used for telephone and SMS is called "secondary card (secondary number)".

When the purpose of the two cards is clear, the most critical step comes: we set the main card (main number) as the default number. If you select "Primary Number" as the default number, it will be used as the default number for phone calls, SMS messages, cellular data, iMessage messages and FaceTime calls. Another "secondary card (secondary number)" can only be used for making phone calls and sending text messages.

On the other hand, if the "secondary card (secondary number)" is set as the default number, the "secondary card (secondary number)" can use telephone, SMS and cellular mobile data after setting; At this time, another "main card (main number)" can only be used for making phone calls and sending text messages.

As you can see, which card is the "master card" has nothing to do with the label, because the label only allows us to better distinguish these two numbers. The key to determine the purpose of "master card" and "master card" is to set them as default numbers.

In addition, if you want to use the "master card" for phone calls, SMS messages, iMessage messages and FaceTime calls when traveling abroad, you can choose to use the secondary number only for cellular mobile data. After setting, the "secondary card" only supports cellular mobile data.

If you want to change the setting of the default number, you can change it in Settings-Cellular Mobile Network.