This is the standard method used on 95% of B311-221 routers. It varies slightly depending on your current stock firmware version (e.g., V100R001, V200R001).
Obtain an unlock code from a reputable provider like DirectUnlocks or DoctorSIM. Insert a SIM card from a into the router. huawei router b311221 unlock firmware hot
The word "hot" in your search keyword implies you want free or cracked . But note: 80% of "free hot firmware" links on YouTube are malware designed to infect your PC. This is the standard method used on 95% of B311-221 routers
The term “firmware hot” often points to (e.g., extracted from an unlocked B311-221) using tools like Huawei Firmware Writer or balong flash . huawei router b311221 unlock firmware hot