Generally with alot of these seeds, i.e. Annonaceae, the germination period or breaking of dormancy can be somewhat annoying. These are a few things I have tried in the past....one I don't recommend in doing.
1) Heat from below with a heat mat.
2) Place in the refrigerator for a period.
3) Pour hot water on the seeds already sown.
4) I have swallowed the seeds before basically mimicking a natural animals response and the seeds obviously go through my stomach acids (I DON'T RECOMMEND THIS)
5) Try putting them in the refrigerator take them out, putting them in a hot warm area outside for a few weeks and then back in the refrigerator.
Some people believe in day lengths, amount of watering and other natural things that can sometimes break dormancy which I tend to agree with but with a fair bit of experience with a lot of Annonaceae species, not necessarily with Annona, but I think most of these species in this family really need to have germination begin as soon as they are from the fruit. I got 10 seeds of Annona diversifolia and within 3 weeks had 2 germinate, the others never did guessing that there was never a well developed embryo in some of the seeds in the first place. The worst I find is Annona crassiflora and Annona purpurea, yet others may find them easy.
I have always found it hard to understand how a lot of these seeds would survive in nature with a dormancy period with insect infestation and other variables. Generally you would think out of the fruit lets get going, but with some species this just isn't the case. My biggest problem is nematodes getting into the seeds, I use to think they were rotting but that wasn't the case the embryo was being devoured by nematodes in masses.
I think maybe just patience is the key, which unfortunately I and probably others don't have.
The other thing is to find out what the weather's like where they are endemic to, i.e. some Africa species have fires run through the bush / forests so soaking the seeds in smokey water or pouring hot water on them can mimic this and break dormancy.
I hope this kinda helps a bit but maybe see how they are in another month or so.