I have a Hovabator, no fan during lockdown. I can't get my humidity to get up to at least 60 percent. My temp is finally up to 100 but the highest my humidity has been is 50% and now it has dropped to 48%. I have a bowl with a large sponge in it soaked with standing water in it. What more can I do to bring up this humidity? I have not opened it and I have both plugs in.