Hello. I use sulphur on all my cuts and mold. Its a very good healer and antifungal too.
Yes, as the others said, scrape away the mold and soft spot and apply sulphur to the area.
I don't like to use tape on the plant bark. I find it tends to pull off more plant bark when you pull it off.
Put some sulphur on a cotton ball and wrap that around the plant and tape the cotton only not the plant bark.
Pull it tight and the sulphur will take care of the mold.
You can find agricultural sulphur (cheepest) in any garden center. and medical grade sulphur at any pharmacy.
Chuck.