I tried several "mildew remover" products.Removed most of mildew,but it grew back.Then I read that u have to kill the"roots",so to speak.
So,I took a deep breath,laid my sunbrella canopy on the paved driveway,on a sunny day,mixed a cup of Javex 5% chlorine bleach in 4gal/15ltr water
& saturated it.Let it sit in sun for an hour or so(sun will kill mold
too),scrubbed it,repeated again, & it worked great for me.No sign of mold
since doing this in June. You may want to test a spot first.Also,you may want to treat it with 303 UV protectant afterwards. / Len