I have a zebrina and it's doing something similar. It stopped growing for months and just started putting out new leaves. Now, I am getting leaves are are very very skinny and short. The leaves look really deformed compared to the leaves it used to grow. Mine is outside in the heat and only gets a few hours of direct sun at most (maybe less).

A calcium deficiency can cause a type of leaf deformation, but I would have to see a picture to be cetain if that is your problem.

Use a hydroponic fertilizer with soluble calcium.

Here are some pictures. The Zebrina looked like it was trying to push out 2 leaves at once. Very pale green and growing to the left instead of straight up. The Enste looks like a jumbled mess. I think 2 leaves may be trying to come out also. I will know more tomorrow.

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Now that I look at the Ensete is looks like two leaves were fused and trying to come up as one. The Zebrina did have 2 comes out at the same time.

Anyone?

That is probably not caused by a calcium deficiency.

Still, with fast growing plants potted in a "soiless" potting mix, it is always a good idea to supply macro nutrients such as calcium and sulfur in soluble form. Often these are not supplied in common fertilizers. I use the fertilizer given in the link below (Note, 5 lb Box) on all of my potted plants. For musa, I use 1 tsp/gal with about every other watering.

Here is a link that might be useful: Hydroponic Fertilizer

Aloha,
It could be BBTV "banana bunchy-top virus" which is a problem here in Hawaii and the plants must be destroyed, but I don't know if your area has any problems with BBTV. You could have them tested before they infect your other bananas. I know it is spread by the banana aphid. Good luck.

Thank you! The newer leaves are looking okay. I think I will try some of that fertlizer. I have a lot of potted plants and many look they need some sort of "boost"

Can over-fertilizing deform leaves too?