Update on BSNL 4G + VoLTE in Thoothukudi
VoLTE is finally working in my location from yesterday. I wanted to share my full experience in case it helps others in Thoothukudi or nearby areas.
Device:
Poco M4 Pro 5G
Initial Issue:
- In Thoothukudi, I was getting BSNL 4G but no VoLTE
- Calls were falling back to 3G/2G
- Speeds were inconsistent, mostly around 1–8 Mbps
- However, VoWiFi was working properly
What made things confusing was:
- When I travelled to Thiruchendur or Sawyerpuram, VoLTE worked perfectly
- Speeds in those areas were much better (10–30 Mbps)
So same SIM + same phone behaved differently depending on location.
What I tried:
- Disabled VoLTE carrier check using Poco dialer code
- Reset APN and changed APN type to:
default,supl,ims
- Kept BSNL as primary data SIM for some time
- Raised complaint in BSNL Selfcare app
- Later raised a CPGRAMS complaint under Mobile Network category
Important observation:
My IMS registration initially was NOT registered in testing menu, but after some time VoWiFi started working. That confirmed IMS provisioning was happening in backend.
Finally:
From yesterday, VoLTE started working in my Thoothukudi location too. Calls are now staying on 4G.
My conclusion:
This was not a phone issue. It looks like BSNL towers in different areas are being upgraded gradually, and VoLTE availability depends heavily on local tower rollout/optimization.
Thanks to everyone who shared suggestions and technical explanations. I’ll continue monitoring speed and stability over the next few days.