Yeah, got the same call. Scammers trying to scam.
I tried to call back using https://www.poptox.com/Canada so as to not let them have my number (it's a free web phone call service) and yeah, phone number doesn't pick up. Probably generated the same way that services like poptox works and isn't a real number even. Someone calls claiming to be CRA, ask if they know your name and info about you, Then even if that checks out, say you'll call them back with a verified number that they must provide. If they give you a number, google it and if it doesn't belong to CRA then its bs. So sad, because this definitely works on people's insecurities and tax anxieties.