The tree might be too young. I would make sure it's getting enough water (but that it's not flooded, of course), try the mulching, spray the tree once every week or two with Neem oil to prevent insect infestation, and consider netting the entire tree if you suspect that animals might be targeting the tree. If the rest of the tree looks healthy but just the fruit are falling, that might be an age thing, and you may have to wait until next year. But probably you can get at least one or two to hold on there this year if the tree's other needs are cared for. (Are you trying to fertilize it? If so, this is not really the time, and sometimes people overdo that trying to help the plant, and it ends up pushing it over the edge. Just give it water, make sure it has enough sun, and if you want to give it any supplementation just give it some light compost or something like vegetable peels that will have to break down over time into the soil, not chemicals and not any huge shot of nutrients that will actually stress it out.)
I have a bunch of seeds recently in the ground, but have not seen them sprout yet, here in extreme SFL. Hoping for a few to sprout that won't mind the conditions we have here.