Looks to me like it going dormant. I would withhold water for a while. It is possible they will lose all their leaves. Most of mine do that, and then do not grow more leaves for about 8 weeks. Your bulb may just be resting. If it were me, I would not worry about. The only other thing I would do is to stick my fingers down into the soil and make sure the bulb is still firm. If it is still firm and not soft/mushy, then I say it is probably going dormant.
