It’s supposed to be a British game played starting from December 1st.
If you accidentally hear “Last Christmas” by Wham playing anywhere before Christmas (December 25)(like at school or the mall) you lose and you have to wait until next year. Covers and instrumentals don’t count, so stuff like Rose’s cover of the song doesn’t count. The Brits are fanatics of this game lol.

I’ve played this since last yr lol. I posted about it too.

There is actually an American version of this game played with Mariah Carey’s “All I Want For Christmas Is You” lol. You have to avoid her song as much as possible.