cannot send gmail from mail on my mac
I have a Macbook Air running el capitan 10.11.6
I have recently upgraded my gmail to gsuite, which entailed a new Google setup.
Having done this I can no longer send email from my Mac.
Every time I try to send it says 'unable to verify account name or password' when I enter the password; and if I go to Accounts to enter it, there is no password field.
I can receive email fine.
I have deleted and recreated the account - still doesn't work.
I have deleted the password entries in the keychain and recreated all email accounts from scratch - still doesn't work.
Any advice?
MacBook Air, OS X El Capitan (10.11.6)