I don’t have an alt, but seems that this should be a priority for the Roblox website
You can make an alt and upload it there, on to your group if you wish. I definitely agree, it is very frustrating, having to wait a long time for something to get moderated, only for it to be glitched.
Hoping Roblox is able to take care of this issue as I need my t-shirts to sell so I can hire a dev to help me on my project asap.
This issue is still not fixed, is there any way to find more information on this bug?
I recommend doing it on another account, otherwise, I have no further information. This is a very confusing glitch/bug, I’m still unsure about other ways to solve this other than upload on an alt account.
Another person with this issue: Configure T-Shirts - #2 by ORdenDev
Try contacting support to report this bug.