The "corkscrew" arm tips are almost always a sign of impending death either from senescence (which correlates with the behavior change), foul water or stress. She may well have already laid eggs and was captured in her end days (often the coloration will be a whitish grey and the mantle will be quite floppy and difficult to control). I suspect this is the case but immediately check your water for ANY ammonia or nitrites to be sure the problem is not that you need more bacteria. Also check the salinity.
Not all animals lose their ability to color in senescence (at one time @Neogonodactylus dobuted that this is a senescent sign - I think now he agrees it is common but may not have been with the species he most often works with in the lab). IMO, the cork screw arms are always a sign of severe stress but senescence is one of the factors that could cause it.
I am happy to report a new addition just arrived on Saturday 6/8 from Liveaquaria. Described as a medium brown octopus from Indonesia. After about a 3 hour drip acclimation he settled in very nicely without incident. He spent Saturday and Sunday tucked away under the live rock and Sunday evening and tonight he came out and spent hours mostly moving around on the glass. I tried hand feeding a piece of shrimp and silverside but he seemed uninterested. I threw in a few ghost shrimp and he grabbed one almost immediately. Here are a few pics and video. Would love an ID if possible
Our Nino was doing great for over 2 weeks.yesterday we 3 weeks since his arrival. Moving around the tank every night and playing. He ate a few fiddler crabs a couple of ghost shrimp and even a small piece of fresh shrimp. A few days ago he stopped eating. Came out 2 nights ago but only for a few minutes and did not make an appearance last night. We knew something was wrong. Picked up the rock where he had his den and he is almost white and appears to be dying. Here is a short video. Water parameters have been very good with vertually no pneumonia and no nitrites. Salinity at 1.024. Water temp has been around 79-80f. I’m at a loss unless he was near end of life when he arrived. Thoughts are welcome. Thank you