In your hosting server when you send a mail using PHP mail function, you specify FROM email address. Sometimes, you might see that mails being sent are from server’s email address i..e. when a mail arrives in your mail box then FROM address has server email address instead of the FROM address that you have specified.
To edit this, create an email address in your hosting account from which you want to send the mail (even if you are not using mail service of hosting provider or you are using different MX records) this may work.