Banana plant issues

I have been growing banana plants for 6 years, learning alot by experience, it's a long story, I bought a young banana 2 years ago tried to grow in indoors in the winter, which didn't do so well, It did survive though but wasn't in a good state, since then the plant doesn't hold it's form in the way of its trunk, the leaves just fall down leaving the plant thin at the top and could snap in a strong wind, Ive noticed this on the shoots/pups I took from It, I discarded 2 as they got really bad bad, but now noticing it on a another banana same species basjoo but no connection to the other ones just planted next to each other, hope theres info out there to help