Rear drivers door open message

[Elliott71]

Ok so a new owner of a used 2014 i3 60ah.
Had this rear door open message come up at weekend and it's annoying the hell out of me. I've tried slamming the door countless times, the warning flickers on and off whilst driving too so pointing towards a wiring issue or faulty sensor switch.
So where is this switch located, is it easy to fiddle with to fix? I'm not in a position to spend anymore money on something like this, but I fear its quite a fiddly job labour wise £££

Or could this be "coded" out in any way??

Car is very cool I must admit, quick, quirky and a total revelation to a confessed petrol head....

 

[EvanstonI3]

I have seen a couple other posts about this issue (not happened to me though). Can't remember what forum/group it was in but basically there is a connecter in the headliner just to the left of center that may be causing this. Not in the hatch, but the headliner in the rear of the car. If I can find more info I will post it.