I haven’t seen this posted yet and it seems to be a combo of two problems.
1. I know of the past bug where Mesmer clones didn’t wear outfits. I wear the ceremonial outfit and noticed my clones were wearing it but theirs was the default dye scheme, while mine was still custom. (Screenshot available)
2. My own outfits eventually lost their custom dye and returned to default. This is occurring on any outfit I try.
I saw the dye bug reported with game crashes; I am not experiencing that.
I have dyed my armor crazy bright dyes in order to more easily see the specific time it reverts to defaults and will post any new findings.