If by mistake you have sent a wrong document to your colleague then you can always write an apology email to him or her explaining the situation and apologizing for the same. This apology email is going to be a simple email which will include the apology along with the explanation. You can also have the right document attached with the email.
We have come up with a format for apology email to colleague for sending a wrong document. You can use this particular apology letter email template for creating a personalized email.
Format for Apology Email to Colleagues for Sending a Wrong Document
I am writing this email to apologize to you for sending the wrong document. I just realized that the document that I had sent you in the morning was not meant for you but it was for Henry Brown who works in the Marketing Department.
Please find attached with the email the right document that was meant for you. I sincerely apologize for this mistake and I hope you will understand that it happened because of same first names. I will make sure that such a mistake does not get repeated in the future.
Thank you for your cooperation and understanding.