Why will my Note 2 stay on the AT&T boot screen even after I take the battery out and turn it back on?

[AC Question]

why will my note 2 stay on the at&t boot screen even after i take the battery out and turn it backon

my phone died and then I put it on charge it booted up but stayed on the AT&T screen ive pulled the battery out and put it back ive let it charge and tried but it will not work please help