Suddenly can’t send email anymore

Hi,

My site suddenly can’t send email anymore.
Yesterday I did every step in here again: https://wphowto.net/gmail-smtp-plugin-for-wordpress-1341
It then worked normally again but this morning the issue came back.

Here is the log when I send a test email:

2017-09-21 00:33:13 Connection: opening to ssl://smtp.gmail.com:465, timeout=300, options=array ()
2017-09-21 00:33:13 Connection: opened
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “220 smtp.gmail.com ESMTP u73sm151555pfi.58 – gsmtp”
2017-09-21 00:33:13 SERVER -> CLIENT: 220 smtp.gmail.com ESMTP u73sm151555pfi.58 – gsmtp
2017-09-21 00:33:13 CLIENT -> SERVER: EHLO toeicmoingay.com
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-smtp.gmail.com at your service, [123.30.157.213]”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-SIZE 35882577”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-8BITMIME”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577250-8BITMIME”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577250-8BITMIME250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-ENHANCEDSTATUSCODES”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577250-8BITMIME250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH250-ENHANCEDSTATUSCODES”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-PIPELINING”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577250-8BITMIME250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH250-ENHANCEDSTATUSCODES250-PIPELINING”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250-CHUNKING”
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577250-8BITMIME250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH250-ENHANCEDSTATUSCODES250-PIPELINING250-CHUNKING”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “250 SMTPUTF8”
2017-09-21 00:33:13 SERVER -> CLIENT: 250-smtp.gmail.com at your service, [123.30.157.213]250-SIZE 35882577250-8BITMIME250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH250-ENHANCEDSTATUSCODES250-PIPELINING250-CHUNKING250 SMTPUTF8
2017-09-21 00:33:13 Auth method requested: XOAUTH2
2017-09-21 00:33:13 Auth methods available on the server: LOGIN,PLAIN,XOAUTH2,PLAIN-CLIENTTOKEN,OAUTHBEARER,XOAUTH
2017-09-21 00:33:13 CLIENT -> SERVER: QUIT
2017-09-21 00:33:13 SMTP -> get_lines(): $data is “”
2017-09-21 00:33:13 SMTP -> get_lines(): $str is “221 2.0.0 closing connection u73sm151555pfi.58 – gsmtp”
2017-09-21 00:33:13 SERVER -> CLIENT: 221 2.0.0 closing connection u73sm151555pfi.58 – gsmtp
2017-09-21 00:33:13 Connection: closed