Looks like heat scorch. What kind of light has it been getting and was it moved or purchased recently?

Its under a houseplant grow light. Its a cutting that I rooted a long time ago. Now I noticed on another hoya plant that it is also tuning brown on some leaves! I just repotted that one :( that one is hanging in my bedroom near a window, but as far as I know it doesn't get direct sun

Could the soil be too wet? gee, I sure don't know, but hope someone who knows something will come along and read this post.

Neysa in California

Does both plants have it on mostly white leaves? The all white leaves don't live all that long typically.
Please post pictures of both plants leaves.

I've seen brown blotches on some of the mostly white/all white leaves of my Hoya before (same one you have, H. carnosa 'Krimson Queen'). It just seemed normal for mine as it would shed one of the mentioned leaves every once in a while. In the winter, it did seem more common though to drop the mostly white/all white leaves when I had it indoors. I don't believe it's anything to worry about unless you notice a mass amount (more than say a two or three at a time).

Planto

Ah thank you guys! I just got rid of the ones turning brown and I did notice that the only ones doing that were pretty variegated. The full green/ mostly green ones didn't change.

Is this normal?

No, it's not. Sorry to say this, but showing us individual damaged leaves tells us next to nothing.

This thread is 5 yrs. old, pls consider making a new thread to ask for help w/ this. Also, pls show pix of the whole plant & its pot, also the soil, so we can try to figure out whats wrong.

https://www.houzz.com/discussions/5774922/hoya-krimson-queen-brown-dots