Issue with adding gmail account

I'm having trouble adding my gmail account. It was on my phone before but was having trouble retrieving mail, so I thought deleting the account and re-adding it might help. Now when I go to Settings>Mail>Add Account, and choose Google account then input my email and password, it brings me to the screen to accept Google's terms, I press "Accept", it briefly shows the screen where you can toggle Mail, Contacts, Calendar, etc. on and off, and brings me back to the screen to choose what type of account I want to add. 2 step verification is turned off and I have also unlocked my account. Any other ideas? Thanks in advance!