cannot add a gmail account

[AC Question]

Trying to add a gmail account into the AT&T Mail app on an Lg 2 Escape. I enter log in info and it keeps saying invalid sign on credentials, try again. I KNOW they are correct...I signed in with same username & password on laptop.
And since I'm here...I want to ask why this phone's wifi does NOT automatically connect when a saved network is in range?
(Not happy & missing my HTC!!)