In the Settings app, you can turn on the old Voice Control (and thus turn off Siri).I had to stop using it - my iPhone was in danger of me throwing it out of the car window.
Just a simple matter of trying to call my mate, who is called Sharon. I say 'Call Sharon xxxx, mobile' and I get 'I don't see Shandy in your address book. I say it again and it comes back with 'I don't shee Shanthi in your address book', it then moves to 'Shandy', then 'Shanghi' then eventually gets the first name right but goes through all permutations of the surname. Meanwhile I'm getting more and more stressed as all I want to do is make a simple phone call!
It used to work 100% accurately before Siri - never got it wrong.
In the end I have to pick up the phone, enter my password and make the call manually - while I'm driving, which I really don't want to do, not least because it is illegal in the UK to touch a mobile phone while driving.
I have a neutral British accent - not Scottish....