She won't give me my phone back?

I let my sisters friend borrow my phone last week for the weekend. She paid me $20 and said she would give it back to me Monday. On Sunday her cousin tells me dropped it in the water so I say it's fine just bring it to me so I can get it fixed and then on Monday her sister and cousin tells me that she got it taken by her grandma so I tell her my "aunt" (which is really my friends mom) is going to go get it and they said that she can't go get it. So I tell them to that I'll buy them an iPhone just so they give it back and then they said okay buy her the iPhone first and be then she'll give it back but I don't think I should have to buy her an iPhone just to get mines back because it's mine. The girl is always posting on her snapchat and Instagram with my phone and she won't give it back. If I tell the counselors do you think they'll help? Or should I call the cops? Please help. I tried telling her to give it back but she won't.

Tell your parents first. Then tell this girls parents? Its your phone and it sounds like she is trying to steal it [for $20]

Take some trollicide.
Anyone that careless with a phone is too young to own a phone.
Too young to be here, too.

Tell the counselors first and if that doesn't work then go to law enforcement

What type of phone is it, you should be able to track where it is if it has power to it.

This is a parent issue, not a school issue.

Go to them and ask directly for the phone back, in any condition, right there, right now. Say that a refusal will lead to reporting it to police as a theft. If that doesn't work, report it as stolen by them.

You need to tell your parents and you all go and directly confront her and get back the phone. If they won't or don't have it, they owe you the cost of a new phone. If you are on a service plan, cancel the plan if they don't give the phone back.

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