You're looking for information on unlocking the firmware of a Huawei B311-221 router.
IMEI-Based Unlock Code: This is the standard method for most Huawei routers. You provide your device's 15-digit IMEI number (found on the label under the router) to a service provider who generates a unique 16-digit NCK (Network Control Key). huawei router b311221 unlock firmware exclusive
Carriers like Visible, T-Mobile Home Internet, or Smart detect hotspot data. You're looking for information on unlocking the firmware
Stability: Optimized for 24/7 performance without signal drops. Package Includes: Exclusive .bin firmware file. Step-by-step flashing guide (USB/Multicast). Dedicated technical support. Package Includes: Exclusive
Open your browser and go to: http://192.168.8.1/html/band.html
If that fails, use the engineering code via telnet:
DC-Unlocker is the industry standard. They sell "unlock codes" and "unlock firmware" for the B311221.