lte 4g no internet cellular data

Has anybody been having Cellular connection issues on their iPhone 6s after updating to iOS 15? I have been having major issues with my 4G connection in India. I use a local Carrier by the name of Airtel. My dad and my mother both have the same carrier but they have iPhone 7 plus and and iPhone...

After days of staying at home, I left for grocery shopping. I took out my phone to google something, but no LTE cellular data was available. All signal bars were there, and I can make phone calls, but can't use data. I have to connect to wifi to use data. I've tried the troubleshooting steps...

For the last month or so I've had extremely poor LTE service at my home. So, I turn it off to just use 4G and the device tells me I have no internet connection. Anyone else experiencing this?