hi guy, sorry you're having troubles.

a couple of things that kinda jumped out at me are that first, your
cuttings are too big, if you cut them smaller, they will root easier.

another thing that might be more relevant to your current problem is
that you have them too deep in the pots, the air needs to circulate
around the plants.

all my stuff is DIY but i think you might find something useful if you
look, especially in my cloner thread.

anyway, good luck