I would be concerned that it is rotting. Did the cutting have leaves on it when you received it? If it did, did you leave them on? Old leaves on a rooting cutting will help dessicate the cutting. I cut off all leaves on a new cutting exept the claws at the tip. This protects the cutting against drying out while rooting.

At this point, since it has stopped developing, I would pull it out of the pot and examine the roots. On a rooting cutting I pull it out of the pot by soaking its current pot in a larger pot of water and tipping the entire contents out. See if the bottom of the cutting has some white roots coming out of the bottom. If it does, I would immediately repot it in fast draining soil and water it well with a B-1 solution.

If the bottom is black and soft with no white roots, I would cut it back to clean white wood and try rooting it again.

If the bottom is firm, but no white roots, it has not begun to root and I would put it back in the same rooting medium, water it once and leave it alone.
Mike

I took it out of the pot, and it had roots 3" in diameter. I kept the leaves on when I got it, should I cut those leaves off.

Not if it is rooting. The roots were white, correct? The stem was firm all the way up? The stem is not wrinkled? If all is OK, you are on the way. I would monitor the growth. You should be able to notice progress at the tip with new leaves emerging regularly.
Mike

It looks real healthy, and the roots are white, and strong. It was completely firm, and didn't have a wrinkle.

She is thirsty, giver her a good drink, then let it dry again.

Karen

Sounds healthy enough. Are there any signs of insects on the leaves, like spots. Look at the underside of the leaves for tiny critters. Some you may need a magnifying glass to see. If the leaves are clean, it may just be stress. Make sure the soil drains well, they don't like a lot of water in the root zone.

Have you moved it to an area with less or more direct sunlight?

Boy, I hope someone else looks at this thread. I'm running out of suggestions.

Mike

Plumeria go dormant when there isn't enough water, they will drop their leaves, inflos, etc. So while it is important not to overwater, it is equally important to water enough. If your plant only has a small root ball I wouldn't drench the whole container, just give it a small cup of water and increase it as the leaves (and roots) grow. As always, let the soil dry out between waterings.

It has no bug on it, and it is growing again. I have three leaves that are splitting all at once. I planted it in well draining soil when I took it out of the pot. I moved it to a place with alot of sunlight, and put it on concrete. I'm letting the soil dry out right now.