u/FaKeShallo

I'll start by saying that I'm no expert and that I've only opened and cleaned it a few times, and each time very carefully. I was cleaning my Special 20 and noticed that the fourth and fifth blown reeds have strange marks toward the ends, as if they were worn. On the seventh and tenth reeds, however, there are scratches near the rivets. I thought it was due to incorrect use of the harmonica and that it might be the cause of some difficulty producing certain sounds. That said, could you tell me if this is normal, what causes it, and how I could fix it?