[Message rejected under suspicion of SPAM] Mailing is now filtered as spam - what should I do?

Question

Yii

Stopped sending any emails from the site:

Swift_TransportException
Expected response code 250 but got code "554", with message "554 5.7.1 [1] Message rejected under suspicion of SPAM; https://ya.cc/1IrBc ...."

Mail settings (Yii2 framework):

'transport' => [
'class' => 'Swift_SmtpTransport',
'host' => 'smtp.yandex.ru',
'username' => '[email protected]',
'password' => '*********',
'port' => '465',
'encryption' => 'ssl',

In the Yandex reference book on this problem, the following is written:

In the mail program I see the error "Message rejected under suspicion of SPAM"
If the message "Message rejected under suspicion of SPAM" appears, the content of your message was recognized by Yandex.Mail as spam. To solve the problem, open the Yandex.Mail web interface and send any one email as a test. This way you will prove to the system that the letters are not sent by a robot.
Also check your computer for viruses with free antivirus programs: CureIt! from Dr.Web and Kaspersky Lab's Virus Removal Tool.

The first advice, they say, go to the mail web interface and send a letter is incomprehensible ... we have our own corporate mail.
The second - there are no viruses, besides, letters are not sent from either test or production.
What to do? Is there any way to tell Yandex that our mailings are not spam?

Answer 1

You have traffic rules, it has a web interface. Log into it under [email protected] and manually send an email.

Answer 2

wait 24 hours and try again, but in general, here it is described in detail how to live with Yandex:
https://spark.ru/startup/pushall/blog/11077/chestn...

Answer 3

https://mailgun.com