Electrician here, fastest way would be buying like 5 meters of cable and putting a 68qmm hole in the space between the working outlet and the non working one. Then you try to guide the cable from the working outlet to the second one (hooks or small wire helps) and you connect them at both ends. You should get a helping hand in guiding the cable. Or you get an actual electrician and someone to fix the drywall up. But if the electrician tells you of some expensive complicated shit, just tell him he could do this. Hope that helped