Some users report success with "default" codes, though this is rare for the B818-263.
Q: What is the default admin login credentials? A: The default admin login credentials are admin/admin. how to unlock huawei b818-263
If you bought the router second-hand or your carrier refuses to give you a code, you can use a reputable third-party code-generation service. These services calculate the official unlock code based on your router's IMEI. How to do it: Some users report success with "default" codes, though