gmail inbox will not update i am using iphone 6plus ios 9.0.1problem started 9/4/15

my gmail account Inbox stopped updating (refreshing) after September 4th 2015. I have deleted the account and set it up many times. under my mail boxes gmail will not update. if I go to my accounts and open my gmail account and click on "all mail" it will refresh and show me my email. but it still will not update the inbox under "mail boxes"