In the seams use the sharp edge of the scraper like a dental pick to force out the moss.
How to get moss off roof youtube.
How to get rid of algae on the roof you could replace all the roofing with new shingles dark enough to disguise the staining or with shingles laced with copper granules which are lethal to algae.
As seen on amazon.
But that would only make sense if the shingles were worn out.
Https amzn to 2ot7kqx how to remove moss and mold from your roof shingles with wet forget some old fashioned elbow grease like a broom.
Climb up to the roof and begin scraping off dead moss from the shingles using a putty knife or painter s 5 in 1 tool and working from the bottom up.