Hi
Here are links where you can find procedure i.e. how to change password on Huawei ONTS.
Article--->https://www.anteny24.com/password-change-on-huawei-ont
Youtube--->https://www.youtube.com/watch?v=4iIZ064 ... e=youtu.be
In our case that is Huawei Echolife Hg8546M.
I also encourage you for further discussion on this topic.