How to choose card 1 card 2 when sending SMS on Apple mobile phone?

I want to change the primary card and the secondary card directly on the SMS page when I send a message with my Apple mobile phone. How to choose card 1 and card 2 for sending SMS on Apple mobile phone? Let's take a look ~

How to choose card 1 and card 2 when sending SMS on Apple mobile phone? 1. Open the SMS interface and click the other party's number.

2. Switch card 1 and card 2 in the calling number.

3. If no message is sent, just switch the card number directly.

This paper takes Apple 12 as an example and applies it to ios 14.7 system.