Lower leaves wilting, advice?

[SalviaDave]

I've taken a few cuttings from the mother plant. They seem to be doing alright so I am not too concerned but I'd like to figure out what is wrong. The mother plant has wilting lower leaves which is gradually (over days) climbing towards the top. Some of them are just falling off, I've checked for white flies or eggs and there are none.

I was wondering if it could be because of this fruit fly infestation I have. I keep having fruit flies (not white flies) they seem to really love sally. I can't see any visual damage that they are causing they just fly around and sit in the dirt, most likely laying larva.

Also it may be that I've potted her too shallow, the root ball starts very close to the surface, only an inch or two down, are deeper pots better?

Anyways, I'll try planting the next one deeper and see how that goes, any rules on planting the stem if it has leaves on it or should they all be removed? Thanks!