Update: I took the plant out of the pot and found these small gray bugs. What are they? Photo attached
I noticed as I came outside that the leaves on my amaryllis were drooping. When I looked at the plant I noticed a white mold/fungus growing in the bottom of the leaves and a little on the exterior of the bulb. I never water the top of the bulb/bottom of leaves, only the soil around the bulb. And only water it once the top of the soil begins to dry, especially since it's getting cooler. It's under a covered south facing patio and gets partial sun in the late afternoon. I'm in zone 10a.
Is this detrimental to the plant or can it be taken care of?

this is some type of aphids, I think, I have hem from time to time on a lot of plants

I spray them with alcohol (or isopropanol) on water (10-15% should be enough). I later found that liquid that we have here that used for washing of glass window or mirrors also do this job.

You have a bad infestation of mealybugs. It is a common and unfortunately difficult pest to eliminate, due to the waxy coating on the body of the adult. I found a good website which might help you. (UC IPM) Univ. of Calif. Integrated Pest Management. The fungus looking patches are egg sacks, the nymphs are colorless and mobile, difficult to spot. This website recommends dabbing rubbing alcohol (less than 70% directly on the adults) this dehydrates them. You can wipe off the egg sacks and spray with a 10-25% alcohol dilution. The issue is burning the plant with too high a concentration od alcohol. With this level of infestation, you need to get under the scales on the neck. Try it for a while, if you can't control it, you may need to dispose of it. Good luck.

Yikes. I have never run into that before. Go for the alcohol treatment for sure.
@sharf - would it be helpful to remove all the leaves and run the entire bulb (upside down) under full running water? And scrub gently with a soft sponge? Would that help to flush some of them off? And then to do the alcohol treatment and replant in new sterile soil??

Cutting off the leaves and cleaning the bulb sounds pretty drastic, but if there is no other choice, I would go for it. I think if you can peal off a lot of the papery scales, which is where they are hiding, and spray thoroughly once a week, to catch each new hatch, eventually you can break the cycle of infestation. Survival will be dependent on how much the plant has already been weakened. The drooping leaves will probably have to be removed but the leaves that are still standing tall should be OK.