Linking to a different Email

[rufiyaa]

Recently, I've been having troubles obtaining the code for authentication when using a different PC (Got a new PC), it seems like it wont get sent on my yahoo.com account, so I created a yahoo.co.jp and im trying to link my account to that Email address, I was able to go past the part with the captcha and was able to change my password, but can someone tell me where I can change the linked Email? I can't seem to find it.

PSO2 account btw