How to find out which network service provider your mobile cell phone number is connected to
- Device Settings
- Wireless & Networks
- More
- Cellular networks
- If dual SIM card then select particular SIM card
- Select Mobile Network
- Choose Network Automatically or Manual Selection
- Click on Manual
- Phone will start searching Available Networks & will show Home Operator first in list and the rest below it
- Select one, and see if it works
- Options may vary by device and Android version.