Nitrates

Soft corals can be tricky. Many of them shed. Which basically means they close up for up to a couple weeks, look rather sickly, then suddenly make a complete turn around (complete with growth spurt). So sometimes the diagnosis for "my leather is acting weird" is, it isn't.

40ppm nitrate isn't horrible for a soft coral. It is high for other corals though, and it doesn't hurt for nitrates to be low (although with softies, you don't want nitrates to be effectively non-existent).

That does sound like a rather high phosphate reading, which could well be upsetting the coral. Do you have any other corals in the tank? That can also be a good guide for judging issue vs shedding. If it is the only coral then I'd get the phosphates down and see if it improves. Otherwise a picture could help judge the overall look of the coral.