May you merge https://android.stackexchange.com/users/5521/kiamlaluno (the current account I am using), with https://android.stackexchange.com/users/4765/kiamlaluno.
As you can see, both the accounts are mine.
I don't know why I keep getting this duplicated accounts. I apologize for this, but it doesn't seem to be my fault; the OpenID I am using should be registered in all the SE site I normally use. The funny is that I have got automatically logged in, as I have already logged in on other SE sites using this browser (Google Chrome), and in the other sites the account I am using is the correct one.