Plant Journal: https://www.plantvillage.com/gardens/228

I noticed these white spots on a leaf of my first and young melon plant (possibly White Honeydew). At first I thought it was the paint from the wall next to the plant but the spots are also underneath the leaf. The plant was spreading directly over the soil, I wanted to put something like hay underneath the plant's horizontal spread but found a dried and fallen betel tree stem today that I put underneath it to raise it above the wet soil. Nonetheless I think it's already catching something even though I have been putting in my healthy homemade compost.

I water it every afternoon cause I have been trying to protect the plant against the neighbour's chickens who'd peck at it and keeping the area wet would repel them so I believe the rest of the day should dry off any wetness that would cause fungus.

Could anybody tell what this is on the leaves?