feathers wont grow back

[shend]

I have a 5 year old barred rock who started losing feathers early summer but they won't grow back on her back, breast and around the wings. It doesn't appear to be a normal molt. Now she seems unbalanced. Never saw this before

 

[Eggcessive]

Do you have any pictures of her missing feathers? Have you seen and feather shafts growing in? Is she being bullied or overmated?