OPPO Reno13 Pro 5G
Selecting dual SIM settings
When you insert two SIMs into your phone, you can make calls and send and receive messages from both SIMs. You can also select a default SIM for mobile data usage.
Slide two fingers downwards starting from the top of the screen.
Press the settings icon.
Press Mobile network.
Press the required price plan.
Press the indicator next to "Enable" to turn use of the price plan on or off.
Press arrow left.
Press Calling.
Press the required setting.
Press Internet.
Press the required price plan.
Slide your finger upwards starting from the bottom of the screen to return to the home screen.