Problems with voice calls on Jio 4GVoLTE.

I was using Coolpad Mega 2.5D since Oct 2016 on Jio 4G network. Voice calls used to work through Jio4GVoice app. Since the update dated 27th Jan 2017 of Jio4GVoice app is asking me to use the phone dialer since this is VoLTE phone but it is very difficult to use the phone dialer for making voice calls. It does not connect unless I disable and re-enable the enhanced 4G LTE mode in network settings.