Didn’t put it as a factor, just a remark, perhaps you should spray some water in the surface instead of watering, that would avoid seed burying and soil being too dump, overwatering is a risk in this stage … 
Didn’t put it as a factor, just a remark, perhaps you should spray some water in the surface instead of watering, that would avoid seed burying and soil being too dump, overwatering is a risk in this stage …