How do I deal with cyber bullying?

I play Roblox with voice chat, people keep on bullying me. I'm already not in a good place mental health wise, and all these words make me even more depressed.
People tell me to kill myself, that I'm ugly, that I sound like a kid (which I do), they call me a dumb bitch and so on. They also talk shit about me to each other.
I don't do anything, sometimes I don't even talk but people pick at me. I don't know why people act like I'm not a person with feelings.
For anyone wondering I am 14 going 15 this year. (I'm born in 2007)
How do I deal with cyber bullying?
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