You can set which card to use as the default card for voice call and messaging. 
	 
 
  
 
	 -  
		  Go to 
				Settings. 
			  
		
-  
		  Tap 
			 Dual SIM Settings. 
		   
		
-  
		  You can: 
		   
		   
			 - Turn either card on or off. 
			 
- Choose which card to use for voice call and messaging. Or select the 
				Always prompt option if you want apps to prompt you to choose a card whenever you make calls or send messages.