Is this root rot in my Phal?

[Tukatuka]

Hi,

I am posting for my Phal that I bought a month ago. It is planted in moss in a plastic container with drainage holes that I cut around and under it. I think it suffered from bud blast and now all the blooms are gone and I have cut the spike at the node under the first bloom and sprinkled cinnamon.

But I have noticed that the moss is always wet even after 7 days of not watering it. We are in Indonesia, it's always hot and humid here (around 90% humidity).

So I pulled the phal out of the plastic pot and saw that a lot of the exposed roots are black empty and brittle. I cut all of the exposed rotting ones. But unsure of some of the green ones. Also the exposed roots are all grey and dry, unlike Phals I see in shops which have green healthy looking roots.

Do I need to repot this Phal? The leaves are nice and succulent, not at all floppy. But there has been no new leaves, instead the old bottom ones are slowly shedding.

If I need to report this Phal I was told by the local grower to repot all Phals in clay pot with moss. Is this true? Can I repot in a claypot wider but shallower than the plastic pot it currently sits in?

Thank you very much for your help.