It could be root rot. Sorry to say. The best option is to check the roots, if they are not rotten then you can pot it back in a pot. Larger if needed, but if not do not go bigger, all that soil will stay too wet. If the roots are too far gone, you can cut off the stems and root them in water or soil, what ever you are comfortable with. The stems root very easily. I rescued one in the same shape as yours from work, cut the stems and rooted in soil, and it recovered fine. It's a little slow as it's winter; but it can survive. Good luck.