Hi-
my rubber roof is in need of treatment. Based on what I had read, at first I thought that the black would scrub off, but as it turns out, black is the color that is underneath the white coating that is coming off when I scrub. I assume the white is a sealant which needs to be reapplied(see photo). Is this correct? If so, what product should I use? Also, how much scrubbing should I do before applying? I’m asking, because the black rubber just continues to break down under scrubbing/friction and is making quite a mess of the sides of my RV. This is the first RV I’ve owned. Thanks for any help.