[General Questions and Answers] monotious:
I just bought my first ever Android phone, Acer Liquid Zest Plus.

It's not quite working in the limited ways I was hoping it to work.

First, I drive a Honda, which has handsfreelink system for connecting the phone to the car. The phone connects to handsfreelink ok, but then shows some weird behavior, in that when using the car's controls to place a call through handsfreelink, handsfreelink immediately apparently hangs up the call (i.e. the car's display shows that it hung up the call). However, this does not actually hang up the call on the phone itself, as the call gets placed nonetheless and when someone picks up on the other side, I can have a conversation through the car's audio system. Seems to almost work, but the weird behavior just described means that I can't hang up a call without pulling the phone out of my pocket and hanging it up from the phone (as opposed to hanging up using the car's controls) while driving, which takes a lot away from the point of it all.

What could be the issue with this? Note that I had a Blackberry Passport before, which used to work all as intended with handsfreelink, and my family member's iPhone 7 Plus also works as intended with handsfreelink. Is it that my Acer Liquid Zest Plus does not have the necessary bluetooth profile/stack to works with Honda's handsfreelink? Is it that handsfreelink proprietary to Honda and uses something unique, as opposed to being a generic bluetooth device of the kind? Is a bluetooth device link this, used by other auto manufacturers, feature the same generic bluetooth thing, or is this something only Holda can possibly answer for me?

Could updating the phone solve this issue? If so, how? I go into Settings -> About phone -> System updates and it tells me that my device is up to date (I did not update it since pulling it out of the box). I notice that it's on Android 6.0 , and a quick Google search showed some discussions that it is highly unlikely that the phone will get newer Android update. The "Android security patch level" shown in "About phone" says December 5, 2016. That's a long time without a security patch. Should I, and is it possible to, update the phone?

I've heard of rooting an Android device and installing custom Roms before. Where can I find a guide for my device and the custom Rom files? I am hoping this might solve my issue with handsfreelink.

I know I am all around the place with my questions, but essentially, the issue I am having is that bluetooth connection to my car's audio system does not work as expected, and I am wondering how I might fix it. I am wondering if an OS update (either official version by manufacturer or a widely-used custom Rom) might solve this issue, or simply adding an extra bluetooth profile to the phone.

A solution would be awesome, but I'd be asking too much if I was hoping for that. Instead, if anyone can just provide me some pointers in terms of how to do research on what I should be doing to solve this, or clarify some concepts (to the extent you can tell I got it wrong from reading this post) for me, it would be really appreciated.

I've already been to Honda's handsfreelink website and Acer's support page for this product and there's nothing helpful there.

Thank you very much.