vinyl siding stains

Homeowner had siding washed, said these stains were noy there when they started the job. Any ideas on getting rid of them? I've tried scrubbing them but they barely budge.

Looks like damage from someone using the wrong chemicals.

It might be chemically damaged, hard to tell with my monitor.

Hmm is there stucco behind the vinyl? could it be the color from the stuck running down?

No, the stucco is below the siding but only painted plywood behind it. Does not seem to be coming from under but this stuff has ruined the siding. I tried everything I have. The only thing that budged it was Xylol, a paint reducer, but it doesn't get it all. we're ok though, I also do remodeling and sold her a new siding job on two gabled ends. It's cheaper to her than me scrubbing for two days.

lester if they are an orangy looking stain I've used Cleansol Bc from eacochem and ran that 4 to 1 and used a rag. then I rinsed it off and it took the stains away. I think it's some kind of clay. At least that's what it is here I think. I believe when they use too much pressure it runs out off the paper they use. Most contractors just throw the paper up and it usually has on it what's on the ground. This is just a guess though.

Have you tried a little oxalic? Sometimes siding bleeds rust and downstreaming oxalic, followed by a good rinse, will correct it. (I have personally had this happen - and corrected it.)