Lock the phone with cloud service
Using Huawei cloud service, you can easily lock your mobile phone. Just log in to Huawei account, select the "mobile phone retrieval" function, enter the login password of cloud account, locate the mobile phone, click "lock device" and enter a new screen lock password to lock the mobile phone. Just use the newly set lock password to unlock the phone.
Force factory settings to be restored
If your phone can't be locked through the cloud service, you can try to forcibly restore the factory settings. Just hold down the key on the tone key and the power key, and select "Restore Factory Settings" to erase the data stored in the mobile phone. Note: It is recommended to back up data to Huawei Cloud Service on a regular basis.