Yeah looks like some nitrogen toxicity.. and if it was me personally, I would probably transplant into a higher quality organic soil or starter seed soil and feed nutrients manually.
If it’s something like miracle-gro, it’s gonna continue causing issues I’d think - especially growing an autoflower. I made the mistake of using miracle gro years back and it burned a photoperiod plant of mine, so imagine it will do worse to an autoflower which commonly requires less nutrients.
I’m really not sure that a flush will help.. that’s why I personally would be leaning towards a transplant. You may shock it a bit with the transplant. But otherwise if you have to flush more than a few times, you’re definitely stunting her and time is of the essence with autos.
Good luck!