Name Change API Unauthorized

So I've been trying to make a program that will let me change a minecraft accounts name using the API seen on https://wiki.vg/Mojang_API and to get the token required to change name : https://wiki.vg/Authentication

But i've been everytime getting the error "Unauthorized" or even"Current IP is not secured" 


and if i were to use a different account than the account i used above

Which seems to work just fine [ NOTE : I made it change to "a" so it wouldnt actually change for testing purposes.

this is the code I made for the change name