I agree
Chante would have been... acceptable. It's the 'r' that bothers me.
If she smiles much at the next lesson I might try and ask (this lady is a strange mix of aloofness and arrogance, but seems to be very fond of children - which doesn't make her very approachable by adults!), and that's why the 'created' name of Charnte seems so odd a choice for her.