How is Cred Garage fetching my vehicle details ??

I was very curious about how they were able to fetch vehicles in my name and just magically show it up! I saw a thread on Reddit where someone said that they were able to access it because we’ve given it access to Gmail! But I have not I’ve not given Cred access to my main Gmail account, only a dummy email that I use for promotional stuff! No access to messages, or phone! Then how did they get it ?