Minecraft skin not showing up in game 2

This is the second report of this issue I had. Please tell me how it's possible to change your Minecraft skin in the launcher. And I tried doing so, but with no avail. I tried with the website, and yet, it didn't work. Do I need to pay for this?

I used both launchers: the legacy one and the crappy-UWP one and it doesn't work.

Can someone explain me this???

oh and the skin i had while changing it it was the default alex one.

Is this a glitch or intentional?

BTW I'm using a MS account I didn't migrate bc I don't have a mojang account.

And mods aren't creating a problem because i tried with OptiFine and without.