Hello. That's a great question, and it's a common and very frustrating one for Android Auto users. You're not alone in this issue. You've done some excellent troubleshooting already, and you've hit on the key problem. The fact that the feature works when you turn it on and then goes away is a classic symptom of a software bug. The car and the phone are communicating, but for some reason, the setting isn't being saved, and it's not being remembered when you disconnect the phone.
The most likely culprit here is a software incompatibility between your phone, which is a Galaxy S9, and the newer Android Auto app. The S9 is an older phone, and the software has been updated many times since it came out. It's possible that a recent update has caused a bug that prevents the "personal results" setting from sticking.
Here are a few things you can try. First, you should make sure that the Android Auto app and the Google app on your phone are fully updated. If they are, you can try clearing the cache and data for both apps. This can sometimes fix a bug that is causing the setting to not stick.
Second, you should try a different USB cable. A low-quality or old USB cable can sometimes cause data transfer errors that could be related to this kind of issue. It's a cheap and easy thing to try, and it can often fix a lot of problems.
Third, you should try to delete the car from your phone's Android Auto settings, and then delete your phone from the car's Bluetooth settings. You can then try to reconnect the phone again and see if the problem persists.
If none of these things work, your last resort is to contact Kia and see if there is a software update for the infotainment system. A software update could fix a bug that is causing this issue. It's not a common issue, but it does happen.
