I dont know why, maybe for the latest software update, i cant make video call without duo because they put duo as default video call😢😢😢 i dont know why they did this as anyone can use duo as it is available and can download it from play store. I think the samsung authority should change this feature and put the previous video call option.
Can any one tell me is there any way to use previous option to make video call except factory reset?
I think that might be the problem. Check the app settings, whether you have set any defaults. Also goto settings>apps>select that app>set as defaults >clear default. Even not solved uninstall the app and restart your device. Just try.