My Calla Lilies need help please

[Iris05]

I’ve done a little research, but I'm still not sure of the right thing to do. My Callas on one plant are turning green and drooping and some leaves are yellowing. I have read that this condition could be due to not enough sun, going dormant, or too much fertilizer. I have used a generic flower food. I don't think I have over – watered.

I have attached a photo, any input is greatly appreciated.
Thanks,

Calla Lily (1).jpg (27.33 KiB) Viewed 745 times