On the website on WP ceased to receive letters in the mail. What could be the reason?

Hi all.
Just yesterday the site stopped receiving letters in the mail with the notification about the order and contact forms.
Moreover, the notification about the order displayed in Woocommerce admin, but on mail the notification not come.
As with contact forms, emails are not sent.
Until yesterday everything worked. No manipulation of the website was conducted.
What could be the reason ?
March 19th 20 at 08:54
1 answer
March 19th 20 at 08:56
Configure mail sending via SMTP. For example, using the plugin WP Mail SMTP by WPForms

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