I would have to say that it's not getting sufficient lighting. When this happens, any new leaf growth will grow limp and be pale green in color. Ponytails love as much sunlight as you can give them during the growing months. But when I bring my ponytails back inside for the winter, they can tolerate being in shadier locations. Also, during the winter months, I keep my ponytails on the dry side. This prevents them from putting out any new growth until springtime.

Unfortunately, this new growth will still remain limp, even in brighter light. But any new growth will grow out perky and erect, with the graceful curves in their leaves. I would scale back on watering your ponytail, to slow down the rate of new growth. Then once Spring arrives, I would place it in direct sunlight [if possible] and begin watering it normally again.

When mine are brought back indoors for the winter, they sit on this table with no direct sunlight whatsoever, receiving only whatever light that my bedroom receives during the daytime. I keep it more on the dry side, almost forgetting to water it sometimes. It does perfectly fine. Then, once the weather warms up and I move it back outdoors, I water it more often at its normal rate.

Thanks for the help! I have moved it to a brighter location and will water it less and just watch it. Yours looks beautiful!