lowlights turning gold, i.e. - YELLOW

I have natural ash blonde hair.  for the past several years my lowlights turn yellow.  hair stylists call it gold, I say YELLOW.  it is not a good look.  no dimension.  my highlights look fine but the lowlights turn yellow, causing a flat overall hair color. I spend 1-2 hours in morning sun.  I do not want to wear a hat.  I like my highlights but the low lights are driving met nuts.  I like the fact the sun is lightening my hair, just do not want yellow color.  my hair is also porous and color seems to fade fast.  I have been to several hair stylists over the years and no one seems to help.  so is the only answer to wear a hat?  could this little sun be yellowing my hair?  could it be my shower water causing the yellow?  should I just try to grow out my natural ash and just do highlights? (this could take forever)

 

  

It will tone down the Yellow but be CAREFUL not to leave it on too long. Because my hair I thought was yellow so I used a purple shimmer lights shampoo and I have purple spots and my ends look grey and purple. Good luck