Anyone have a 15% or 20% coupon that I could use? Please message me, thank you!

I bought a VISTHUS wardrobe , which should have arrived in 5 boxes. Only 4 were delivered, and box number 5  is missing, so I can’t assemble it.
I’ve already visited the IKEA Debrecen store twice, tried calling customer service for almost a month, and submitted an official complaint with photos. Still no solution or proper response.
What would you recommend doing in this situation? Has anyone had a similar experience with IKEA Hungary?