It's a little difficult to see detail from your photo, but let me make a start.
First thing I'd do is to unpot it, and get rid of all the existing compost so you can see the roots and the neck of the plant. Check the roots and the body of the plant for bugs. Most common is mealy bug mite.If there are some.then use an insecticide to kill them.
Check the roots and remove any dead bits. They and the neck of the plant should look healthy and be just a bit spongy, with no rot or not dried and hard. Rot can be cut off but if the roots are hard and brittle and the neck feels really hard, then it may be too late. But anyway then repot in fresh compost and hope it comes back into growth.
If it doesn't respond then I'd unpot it again, recheck, and either repeat, or more drastically take a sharp knife and cut the roots and neck of the plant off. You can then see clearly if the plant is dried up or if there is sap showing there is life. If alive, let it dry for a week or so and put it on a sandy compost and with luck new roots will grow, but this could take several months.
The fuzz you mention should just be wool, but if it isn't then you could have a bad case of mealy bug, spray it well and several times over a month or more.
Hope this helps, but others might have other suggestions.