card phone. I'll demonstrate this process on Samsung Galaxy A3.
- Go to the app list and find Settings.
- Select Settings, then slide right to find and select Sim Card Manager.
- You'll see a list of subfolders in this section. Slide right again to see "Sim1" and "Sim2".
- To activate or deactivate one of them, double-tap the chosen sim card, e.g. Sim1 to open it.
- Slide to the right to check for its current status. If TalkBack says "On Switch", that means Sim1 is active and can now receive calls.
- To deactivate it, slide right again to turn it to "Off Switch" state.
Note, if your phone is running various apps at the same time, there will be multiple app pages on screen. Slide 2-finger right or left to switch forward and backward among pages.