Yeah we can select sim. But then all the calls I make will go from that default sim. If we select the option of ask everytime option, it asks me from which sim to call everytime, but if I did not select within 5 secs it has to make call from my default sim selection after certain time, so that I can differentiate the SIM from which I can call for office numbers and family numbers easily. This feature also helps if we are using Google assistant to make calls handsfree and also in times when you can’t reach your phone.