My purchase of minecraft does not show up on the website.

I've had Minecraft for about a year now, I've playing on Nintendo Switch. There hasn't been a problem but i recently have been wanting to make a skin, so i decided to go to the website and try to see and how to make one but it says i have not purchased Minecraft when i know i have.

That is my only problem, id just like to know why i says i havent purchased minecraft, if you could please fix it that would be great or tell me what i have to do to get it and make a skin.