Use Google Assistant with screen OFF Samsung S7

[Android Central Question]

My Samsung S9 "wakes up" with the "ok Google" command quite happily and within the Google Assistant settings it says: "Access your Assistant any time that you say "OK Google", even if your screen is off or you're using your favourite apps". Running Android ver 9.

My mum's S7 says "Access or your Assistant any time your screen is on". Now I have NO security set on mum's phone (swipe only), so this isn't related to the removal of the assistant to unlock your phone.
So when she's driving, she has to wake up the phone first (by hitting the home button) before she can ask Google to make a call.... this kinda defeats the purpose.
Android ver 8.

What am I missing? How can I make mum's phone access the Google Assistant when the screen is off?

 

[dekatch]

voice Match?

i have this setting available on my note 9 android pie, and it allows me to use Google assistant when screen is off and locked

it says 'mit voice Match zugreifen'
translates to 'access via voice Match' or something similar

you'll find this setting when you enter Google assistant / settings / assistant / voice Match

 

[Purrsia78]

Yeah, I have that on my S9 too...

The problem is that on my mum's S7 the ONLY option is "Use the Assistant when the screen is on" - I can't make it work when the screen is off.