Question about changing forum glyphs (PC and Switch account share the same forum account)

[_-Friendship]

So I have a PC account that was made 5 years ago. But I only really got back to the game when it got released on the Switch. I didn't migrate the account but I use the same email. When I log in to the forums by entering my email and password, my forum name uses the PC IGN and glyph. But if I log in via Nintendo Switch account, it's still the same account but it uses my Switch IGN and keeps the PC glyph. How can I switch to my Switch glyph? 

 

EDIT:

Here are two screnshots that'll hopefully explain what I mean:

Edited January 24, 2019 by _-Friendship