Okay so, this is sorta complicated.
So there are 9 default skins in MC ( as of 1.19.40)
I'm not 100% sure if this next part is accurate
I think the skin is always named Steve if u are not signed into your account. Regardless of whether the skin is Steve or not. The skin is randomly picked from the default skins if You are not signed in.
So, it isn't a glitch