Launcher keeps changing to custom skins

Hello,

 

Since a few days, Minecraft has been changing my skin to a random one every single time I try to use the skin I normally use. I have re-installed my launcher and changed my Microsoft password, but it still happens.

Does anyone know how to fix this? 

 

In the image you can see a skin that has been selected by Minecraft against my will, and the skin I drawed a circle around is the skin I want to use.