Q.A problem with my calla lily
I have it on a covered porch and water it every few days but it is dying. Any suggestions?

There are many things that could be causing this. It could have too little water, too much water, pests, fungus or an environmental issue. I would recommend that you look at the standard care practices for calla lilies and make sure that you are doing them and, as a precaution, you treat the plant with a fungicide and a pesticide.
This article will help with calla lily care:
https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/growing-calla-lilies-and-care-of-calla-lilies.htm