Try to dry them out as much as possible - maybe add a layer of vermiculite on top of the soil and definitely don't water for a while. You could also rub or pick the mold off.

You may be able to obtain a liquid fungicide called No Damp. It is made in Canada, you might be able to get it online though, and I use a syringe that you can buy in a drugstore to
apply it. I apply it undiluted to the growing medium, or you could dilute it (but still apply it about twice as strong as what the label recommends) and drop it directly onto the seed. Sativa.