Elephant

Hello all. I don't know if this is the best place but I need some advice and don't know where else to go. For a while now, there have been a group of kids on this website I frequent that have been harassing my friend and other people very severely. It's mainly 2 of them, and they have been sending my friend pictures of self harm with the intent to trigger her into cutting herself, making fun of her in various ways, and even posting her (and others) personal information. This is not the only time this has happened and they have done even worse in the past. The thing is, when I and others have reported this behavior, the staff on the website has done NOTHING to stop it. I want something to be done about this, before they push my friend or someone else too far. Is there anything that can be done?