Very nice A. humilis colony, Parraman !
It is, however, exhibiting strong signs of RTN ... Likely from stressors related to lack of flow and/or light, as this species is a reef crest species which demands high flow/light and perfect parameters.
Personally, I would fragment it out ASAP, as it can/will RTN faster than most other species of Acropora, trying to save a few outer branches in the process.
While this is an added stressor, I believe, based upon the provided photo, it will fully RTN under current conditions within a matter of a couple days.
Best of luck in your endeavor to save this beautiful specimen !