(Ommmmmmmmmmmm - chants to remain calm and serene .....

)
tl;dr - if you can't already see your bound car in the app, you're logged in to the wrong account.
If you've previously used the app, and can no longer use it in the new version, but you are logged in, then ...
you are logged in to the wrong account! Simple as that.
You MUST login using the
original details you used when
creating your account. If that was via email, use that ... if via phone number (without the leading 0), use that. I don't care if you've previously been able to login via either method in the old app, you MUST login (first time) using the original login details.