My tree in 3rd of 4th year, 100 or so flowers passed through, no fruit set yet. Been taking advice on forum read before and trying to attract bugs, but so far dealing with the tree ants who keep coming back to the tree to build a nest. They seem to be guarding the flowers now, as if the pollination wasn't difficult enough already.
Sugar Apple trees on other side of property fruiting well, perhaps since my soursop is seed grown it is waiting on some genetic code to produce...