At that moment, I felt like throwing away my Hamelia patens but I took control of my emotions. Eventually, I traced it back to the stem and prune it off to prevent its spread. Sometimes I hate the ants because they love to culture the mealy bugs and scales.
In the last photo, the Curcuma longa is growing well even though I didn't purchase it. It was a stowaway on the Afgekia sericea that I bought from Ang Mo Kio Flora.