Since Google released Android 12, there have been a number of issues with Android Auto, including a bug that caused the navigation feature in Google Maps to stop working for some users. Another issue that has surfaced since November 2021 is a bug that prevented notifications from appearing on some users' head units when new messages arrived.
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The giant has now fixed the issue. A Google spokesperson confirmed that the team has “implemented a fix to resolve this issue” in response to a post on the Android Auto help page.
A user complained via a forum post that the error appeared after updating a Samsung Galaxy S21 Ultra to One UI 4 based on Android 12. Other Samsung phones, such as the vanilla Galaxy S21, were also affected by the issue. The user made the following comment:
For the past three weeks, Android Auto has stopped showing new text messages or other notifications. If music is playing and a new message appears, the music pauses for a moment as if to let the new message notification be heard, but there is no sound and no message on the auto screen, even though new messages have arrived on the phone.

See also: Android Auto users complain about Google Maps
It's unclear why this particular issue occurred as Google didn't provide an explanation. However, what matters at this point is that the bug has been resolved.
If you had the same problem, you should update your Android Auto app and messaging app to the latest version in order to get Google's fix.
Information source: androidcentral.com
