If it's still extending it's polyps it's probably not as close to demise as you might think. With that said, this coral will sometimes retract its polyps for days at end. Generally (if it's requirements are met, basically the right water conditions and sufficient lighting, this is a very hardy soft coral).
If this coral is new, it may need a few days to acclimate to your tank. How long have you had it? When it rebounds it will be able to straighten out.