Gmail can't send out from Iphone 8

Hi All Expert,

Good Day.

I am getting "The connection to the outgoing server "smtp.gmail.com" failed." when sending gmail from my iphone 8, no other configuration was done just from the mail select google and login with gmail email address and password, previously was still fine, but it sometimes cause issue with my company email, which one fine and another not. Appreciate if expert here can assist me on.

Thanks!