When I try to open Minecraft, I can play in my worlds, but it displays my gamertag as "SkinStandardCust"?

Before the latest update, it did keep saying I was "SkinStandardCust". When this happened though, it only used to be there for like, ten-ish seconds, then it would go away, especially if I went into my Wardrobe first, and then exited out (even if I didn't actually do anything in the Wardrobe at all). Now, it stays there for like, forever. In the previous update it would actually also display my name in-game as SkinStandardCust, meaning that if I messaged someone something, it would say the message was from SkinStandardCust. Haven't tried this out on the latest update yet but may still be a thing.

This is a bug that seems to happen the most when I first launch Minecraft for the first time since turning on my computer.

Thanks <3