"From" e-mail address

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this is WordPress's default beahviour, and your sender email is from wp-admin >> General >> Settings  > Site Email. 

But you can override it 

Please use this plugin >> https://wordpress.org/plugins/wp-change-email-sender/

So you can change WordPress sender email and name. 

Make sure your From email is related to your domain name to avoid your email going into SPAM of recipients. 

Using This plugin enable you to change mail sender name and email address from WordPress default mail sender name and email.
After install go to Settings->General.