I have the G. speciosum which doesn't appear to be the same as yours. The speciosum likes full sun but the others prefer a bit more shade. That might be the problem with yours. Try it in filtered light and see how it goes.

They also don't like to dry out. I would repot it in spring or trying putting it in the ground.

You don't say where you live, but in Florida many people grow them successfully in the sandy soil we have.

Jane

Thanks. I'm in Coral Springs, north of Ft. Lauderdale in south Florida. The bigger bulb is still hard, but the smaller one that is dark is very soft. I'm going to repot it and cut off the rotten sections today. Might end up with two divisions, which I will grow with more shade. I'm finding this one to be a frustrating and challenging plant, which is ironic given how easy its reputation is.

Do you know which species yours is?

Not sure.

When you cut the rotten parts off, make sure you sterilize your cutting blade first. You don't want to risk an infection to your orchid. :)

Use rubbing alcohol or bleach, anything that sterilizes it.