Unable To Sign In To Xbox Live (MCPE For Android)

I tried multiple times resetting my phone, uninstall and reinstall, etc., but nothing worked. On the page, sisu.xboxlive.com, I clicked "Sign In", it brought to another page where it asked me if I was trying to sign in to MCPE For Android, I clicked "Continue". Then it brought me to the page, sisu.xboxlive.com, again. So I clicked "Sign In", it brought me to a page where it asked me if I was trying to sign in to MCPE For Android, I clicked "Continue", then it brought me to a black screen where I been stuck on for so long.