Most of the pocket wifi use the standard access or the setting configuration 192.168.1.1 address though other use 192.168.0.1
To change your password try to follow the instruction below:
1.) using your android/IOS or even notebook connect to your huawue portable wifi device
2.) Open the internet browser usually displayed as "world icon" and type 192.168.1.1 if you could not access then try the alternative shown above
With that you steps, you could be directed to the device platform where you could change all the setting including the password.
I hope it could help you and have a great day ahead.