When I turn the car off, the rear lights stay on, what could be the problem?

Faulty switch, or you have a Body control Module communication issue. You need an auto-electrician with a pro grade scan tool computer to check live data and communication between all the systems.

Or it is the Parking Light secret switch!!

https://howtune.com/articles/239-subaru-lights-stay-on-and-won-t-turn-off

https://www.google.com/search?q=2008+Subaru+Forester.+The+parking+lights+and+rear+tail+lights+stay+on

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Normally all parking lights are controlled by the light switch. First turn turn on the parking lights and second turn turns on the head lights.

Are you sure it is not your break lights staying on? if this is your break lights - look at break pedal for break light switch staying on or not adjusted correctly. Does your car battery gets drained from your break lights staying on?

Sounds like the brake lights are staying on, which is probably a faulty brake light switch on the pedal.

lol sounds like my old truck most likely crossed wires

faulty connection ,or check all your fuses from box,check fog lights fuse 1st,

Make sure its the tail lights and not the brake lights. Problem could be brake light switch or lighting control module.

sounds like a bad headlight switch, when lights are staying on unplug switch ,if lights go out then replace switch, good luck.

change the brake light switch on the upper part of the brake pedal

Your car has rear fog lights. The rear light that you see come on with your headlights is your rear fog light. The light in your dash is the rear fog light indicator. To turn off your rear fog lghts push your headlight switch in half way. To turn off your front fog lights push in all of the way.

hiya if the rear lights are remaining on ? with no ignition it will be the brake lights staying on this is easily remendied/ checked by trypulling the brake pedal up by hand and see if lights go off ? if so then you will need to adjust the b/light switch which is positioned adjacent to pedal and can be screwed inwards towards the pedal untill the plunger on switch is pushed into the switch which puts lights off ensure pedal is fully up then adjust switch reconnect the wire/plug and press pedal slightly to ensure b/lights operate ok and then go off with pedal released ? on hyundai the brakelights do not req ignition on to operate hence more likely problem is as above good luck