How to change sender email in WordPress?

Question

WordPress

Greetings.
We made a copy of the site on WP, deployed it on a new .RU domain (it works the same way with the old .COM).
Letters come from a new site that is on the .RU domain, but from the sender of the old one. In the settings I changed the mail address (confirmed, the mail has changed). Does not help.
What did not help yet
1. Replaced all references to the old mail in the database, crashed all the pages created by this user, checked the sending from the form, the letter came from the old mail address.
2. Did a search for the old mail address in the files of the site, does not find it.
3. I installed the CB Mail Sender plugin, it does not help.
4. In functions.php I wrote:
a)

// Функция для изменения email адреса
function devise_sender_email( $original_email_address ) {
    return '[email protected]';
}

b)

//изменение имени и email писем start 
function change_fromemail($email){return '[email protected]';}  
function change_fromname($name){return 'New name';}  
add_filter('wp_mail_from', 'change_fromemail');  
add_filter('wp_mail_from_name', 'change_fromname'); 
//изменение имени и email писем end

I am looking for support from you, the left eye does not give rest (twitches)

Answer 1

Most likely there is some kind of plugin, where the address of the sender of certain letters is specified in the settings. For example, the Contact Form 7 plugin can be installed, which displays forms in certain places on the site. In the settings of this plugin, the address of the sender of the forms of this plugin is specified, so your manipulations with changing the sender in other places do not help.
Update
If Contact Form 7 is installed -> plugin settings -> select a specific form -> open the "Letter" tab -> edit the "From" field.
If this applies to emails from the Woocommerce plugin -> Woocommerce -> settings -> Emails -> scroll down -> edit the "Sender Address" field.