I believe a similar bug report was made here, though they’re using an extension so it’s slightly different.
On both the mobile app and the Roblox Player, you have the option to change your skin tone to almost anything with the skin tone slider.
The issue is that if you wear or create an outfit that uses the skin tone slider, through the website instead of using the apps, it will overwrite the skin tone with one of the basic body colors instead of the one you chose through the slider.
Creating an outfit
Outfit created via the app
Outfit created via the site
Wearing an outfit
The same thing happens when you use the site to wear the outfit that was created on the app too:
This seems to just be an issue of the website not currently supporting custom colors from the slider.
A private message is associated with this bug report