Upon visiting Roblox’s support page you’ll notice one thing, imputing an username is optional but is usually supposed to work.
However as of recently this has been completely broken and prompts you with the following error when trying to submit.
I always used to submit my tickets this way until it broke.
Expected behavior
Viewing the steps into getting this error and how it is supposed to work, you should be able to submit a Roblox support ticket without imputing a username like you always could’ve prior.