Can't add Gmail account to Mac.

Good morning...I am stuck! I changed my Gmail password yesterday and can no longer access my Gmail account through Mail. My Gmail account would show the little 'Lightning Bolt' when I opened Mail, and would not sign in. I have removed the account and tried to re-add it. When I attempt to re-add the account, all appears well as I add the Account, Password, and 2SV code I get via text. Then when I attempt to finish the process I get an error from Google that says '400. That's an error' (See below). The account is still active as I am able to access it through my iPhone mail and trough the Gmail website...it's just when I attempt access through my 'Mail' app on the Mac. Any assistance is GREATLY appreciated! Thanks in advance.