Natural Match in #9 Ash Blonde

I am 53 and have very fine hair with 25 percent gray . I am very fair with a cool skin tone so I like very light ash shades that will complement my colouring plus cover my gray. I purchased this...

I have only one quibble with this product; it doesn't fully cover grey hair. I have a spot on each side of my temples and although the colour works for 2 weeks, it fades quickly & grey shows....