Smoke smell in apartment

I just moved into a new place and didn’t notice it when I toured the place, but one of the bedrooms smells like smoke. They replaced the carpet and painted the walls, yet the smell remains.

I put in one of those heated oil air fresheners, I hit it up daily with some Frebreze-type shit and leave the doors to the balcony open when I’m home, but it’s still there. Any tips?
You should’ve told them to give you the money and you’d replace the carpet yourself. Chances are they probably didn’t replace the padding.