Did I err in publishing a fatwa on the prohibition of lying in jokes on a WhatsApp group, knowing that the goal is to generalize the benefit?

There is no blame upon you for what you did in clarifying the impermissibility of lying and alerting everyone to it, for it blocks the avenues of evil and closes the gates of Satan. Allah Almighty says: "O you who have believed, do not follow the footsteps of Satan." The Hadith (definition) indicates that the liar whose lie reaches the horizons will be punished by having the corner of his mouth, his nostril, and his eye torn to the back of his head. This can happen with the spread of lies through communication means like WhatsApp.