My friend had her warrior of light deleted by her brother because he thought it would be funny, she had no idea it was him so she was afraid she got hacked or something trough some days. I made threads about this on reddit and she's called square enix support a lot for this plus filling the forum to get your character back but she still hasn't fast forward a couple of weeks and she gets a reply from square enix customer support that says she missed her 24 hour window (She hasn't make a backup either).
Please if anyone from square enix sees this help her she really loves the game so much