Advice on removing low lights

[Kenna]

1. Hi guys
   
   Basically I had very bleached blonde hair & asked a "friend" I used to work with to add a few low lights to make it look more natural & the result I got was a dull greyish colour.
   
   I was thinking of bleach bathing it out? Or add some bleach foils over it?
   
   I'm gonna try head & shoulders first but don't think it will get my blonde back!
   
   What do you think?