Garden Pests and Diseases: Problems with once very healthy African milk tree, 1 by Jsta04

Jsta04 wrote:
Hi there,
Any chance anyone can help me.
It’s been really healthy its whole life so far with all its leaves and a beautiful deep red color. Recently I noticed some leaves shriveling up and don’t think much of it as it’s winter here in NZ and not as warm or as much sun. But then it started dropping ALL its leaves and I noticed a scaly scabby patches up the plants stem (see pictures) as well as some black spots and discoloration on the leaves.
I do not believe it’s over watered, the plant isn’t soggy and the soil is totally dry.
Any help would be greatly appreciated.

I did repot it just before Christmas and it really thrived. The new growth was thicker and it grew really fast, until this disaster stuck around a month ago.

Thanks