You are not alone if this has stopped working.
Earlier this week, Android Auto 5.0 was rolled out and the update included a new feature that lets you turn off notifications while driving.
A handy feature that definitely has the right to life, but the rollout also brought with it an unfortunate consequence for many users.
It turns out that the launch caused the buttons on the steering wheel, which allows you to accept or reject incoming calls, do no longer work.
Many users have reported this on various forums, including Reddit. The error comes after the installation of Android Auto 5.0.5002, and so far Google has not addressed the issue publicly.
A temporary solution that can work
You can always use the touch screen to answer or reject calls, but this is not optimal as long as it is much safer and better to control it via the buttons on the steering wheel.
Some users find that these buttons work again after disconnecting the phone and reconnecting it. So in the meantime, there may be a solution. This case is updated if Google provides an explanation and / or a bug fix.
Have you noticed anything about this?