cincinnana

Pat

What has happened is that your P-stem has been damaged.
Note on your plant that there is damage right above the "blow out". See the dent and black area of your banana.
As with your plant as well as others the new growth will take the easiest path of resistance---the weak part of the P-stem.
Soon the new P-stem will cause your old growth to act like a old leaf and eventually slough off just like the others.
I tend to chuck my plants by the stem when moving them and sometimes I damage the stem and this is the result.
As the other fellas stated in previous posts this will indeed "sort itself out"

Happy Gardening!!!

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