How do I remove smoke residue from walls?

We do this in our rentals. https://www.mollymaid.com/practically-spotless/2017/august/how-to-clean-flat-paint-walls/

Hope this helps https://www.goodhousekeeping.com/home/cleaning/tips/a12438/stains-smoke-may07/

They can be “washed down” with a Spic N Span solution. It’s tedious, but cheap on flat walls.

There are chlorine dioxide tablets made for “fumigating” hotel rooms that have been smoked in. They can be bought on-line. One has to get the plants & pets out of there, along with the people - for at least 4 hours.

Like any other fumigator, it takes other important preparations.

As a former apartment manager, flat painted walls don't wash up too well and are porous enough for odors to seep into the drywall. Hence most apartment we rehabed after a smoker required 2 coats of primer and a top coat of paint. Also usually just replaced carpet and drapes. Room Shocker is your best bet to get the odor out. So you might want to resign yourself to losing your deposit.