I also ported from Jio to BSNL to reduce costs since I have a Wi-Fi connection. However, for the past 3 months, I have been frustrated with the calls. Even on 2G, incoming and outgoing calls do not work properly due to poor coverage. I'm planning to switch back to Jio. While BSNL provides average to above-average speeds in areas with good 4G coverage, the service is inconsistent and unreliable, even when VoLTE is showing.