I'm hoping for some help if possible?
My wife bought me a Carmona Bonsai tree for christmas but all the leaves have already wilted / gone brown and dropped off. I think I have overwatered it, is there anything I can do to revive this tree or is it too late ?

I have no real experience of bonsai's, this was my first attempt and it looks like it's gone horribly wrong !
Thanks in advance,
Matt.