FIXED!
@OreotheCat tell them to try fix it over the air for you so you can save the trip to Tsuen Wan... unless you want to go there... haha
I took it to the service centre y'day and they fixed the charge port door issue almost right away! (took like half an hour for them to park my car and run data)
Service told me initially that the fix may take a day or two but turned out it was only a matter of setting for the charge port door sensor. The engineer simply set the sensor sensitivity higher and problem was fixed (meaning it could have been done over the air)
Obviously if the sensor is dead then it's a different issue... but one test you can carry to see if it was a dead or insensitive sensor is try pushing the charge port door in fully (completely compressing the spring on the car magnet) and watch your dash or centre screen to see if it senses the charge poor door closure. In my case, before the fix my car was able to sense the charge port door closure when the door is pushed and held in, indicating it was an insensitive sensor rather than a dead sensor...
Really hope this helps as it kept me annoyed and confused for days!
Now everything is so much better having the left side of my dash back where Navi instructions and "now playing" is shown! And of course not needing to guess if my charge poor door is indeed open or not...