Newplast Plasticine, Orange Block of Modelling Material

I have ordered Newplast before and it has worked fine. But this block is really hard. I can soften it, but that's not the problem. The problem is that it seems dried out. I can't work with it because it keeps cracking and falling apart. I tried adding canola oil, soaking it in warm water, and adding Vasoline, but it hasn't worked. I don't know if I didn't let it sit for long enough, but those methods didn't work.