oh, and just to be more specific, it's mainly the new growth that is so bendable. The bottom of the trunk is hard.

I don't think there's any way for us to know whether your potting soil is dry or wet. You'll have to check it yourself.

Are they indoors or out? Do they have leaves yet?

You don't say where you live or what your temperatures are.

You could carefully slide it out of its pot and see what the situation is like.

I would check down in the bottom of the pot - maybe just take the whole thing out and examine the soil and the roots for any rot. I would go ahead and try to amend the soil with some added perlite or something if it's to peaty and wet and get it in well draining soil.

If your plumie has enough water then the most common other 2 things that could affect it are too much water and / or cold. Is there any discoloration on the tip or part that's bendable? Is it getting enough heat?

If you don't see any rot after your exam I would just keep an eye on it, if you see anything dark or rotten then it will need to be removed.