Able to text and use internet, but no phone calls

It is a refurbished Yureka Note. I added a newly activated sim in it. It's sending and receiving text messages. After saving the gprs/mms settings sent by mobile operator, I am able to use internet (which is pretty fast) as well. However, despite trying variety of things, I am unable to make or receive calls on it. When I tried calling it from another number it says: outside network coverage. Given that signal is full, my guess is that this has something to do with no VoLTE support in this phone. I tried many options from *#*#4636#*#* also. If I select WCDMA/GSM only then there is no signal. When I use LTE only, there is signal but calling *to* it says Line Busy. Is there any way to make calling work on this device with this sim?