If you come up with better insults/comebacks than them, that should shut them up. One of my favorites is "I could eat a bowl of alphabet soup and look in the toilet an hour later to find a more educated response". You should also pray for them, that they see how they might see how what they're doing isn't right in God's eyes. But if you want them to stop, the whole letting them know you sympathize with them doesn't work. Really all I can say is assert your dominance, and try not to take their stings personally.
I don't know, though. Lol

Sadly, bullies only care about inflicting harm on others, whether for their own pleasure or to amuse their "friends". They need to put others down to feel better about their own shortcomings. They are broken and in need of help and prayer. Tell them you feel sorry for their pain and that you will pray for them and mean it. If they continue in their harassment, block them, but continue to pray for help for them.

Thanks

I have low self-esteem and I'm not a bully. The truth about bullies is that they're usually very happy with excessively high self-esteem. Sadness usually makes people shut down and withdraw, whereas bullies advance towards and lash out at who they don't like.

This also happens. It, too, means they need help and prayer. I disagree that it is usually for them to be very happy, outside of their putting others down and the "happiness" that stems from it. Regardless, a person that enjoys or routinely bullies others, by definition are in need of prayer.😌👍

laugh at them
don't respond to them
report them
or mock the ever loving HEEEECK out of them