Birds tail feathers growing in wrong

[Maya The Ringneck]

When I first got Mya she had tail feathers that had grown in weird and curled to the side at the end of them.
We had them trimmed and they were looking better, but they look to be starting to curl at the ends again. She does
chew on them a bit and she has broken a few before but I do not know if that is the cause of the curling or not.
I just want to know if that is like genetics or if it is something that i am doing or she is doing to make them curl at the ends.
Please let me know what you think it is!!