Hi stoofers, Welcome to the site!
I agree with Gina, your plant is staying too dry which is likely the reason the one stem dried up. That stem will not recover, is no longer viable and you can snip it off. It appears your
Wax Plant (Hoya australis subsp. tenuipes) is in a terracotta pot and the soil does look a bit on the dry side. Hoya australis likes a chunky, well draining potting medium and bright light. Since terracotta does tend to dry out rather quickly, you will have to adjust your watering routine accordingly by watering more often.
Hoya australis is one of my all time favorites, mine usually blooms from November to February and the flowers are very fragrant.
