Does anyone else is also experiencing the same problem like I have? Otherwise, how do you work around to unlock your phone with Google Voice Match successfully. I understand that Huawei do have similar feature built-in into our phone, but I prefer to use Google’s one. Now I wonder if Huawei is impeding that function purposely in order to promote to use with their own Voice Wakeup function

Best answer by RussH
If you use voice on your phone you probably depend on it, especially if your a driver. So this problem NEEDS to be resolved!
And I've fixed this!!! -Twice! I think with this issue there are two problems running together. The first can be resolved with the favoured solution above that involves going into phone settings > apps > Google > clear cache and data. For me, the problem recurred, and it did not resolve Voice unlock, so here is what I did.
If you have enabled 'PrivateSpace' on your phone, then you are essentially holding two devices in you hand, and if both your 'Privatespace' mode and your normal mode phones are signed in to your google account, then there is a conflict about which mode the phone opens in when it responds to you saying 'OK Google'.
Therefore, try going into your 'PrivateSpace', open your Google app, press 'more' in bottom right of the screen > settings > accounts and privacy > Google account > SIGN OUT. If you want to have a google account in your private space you will probably need to set up an alternative 'private' google account and disable the voice unlock on that account to ensure that conflict didn't reoccur. Also make sure voice id off by going into the google app settings (in Private mode again), select 'voice' > Voice Match and toggle all switches to off.
Return your phone to normal, none-Private space mode. Try your voice unlock, hopefully it will work. If not, clear the Google app cache and memory again. Because you will still be signed in to your Google account when your phone is in regular mode, when you set up voice unlock in your signed in regular account it will work properly as there is nor only one 'device' that is set up to respond (ie your phone in normal mode, no longer the phone in PrivateSpace mode).
I hope I haven't made it sound more complicated than it is!! Good luck.