If you have emailed a contact via your CRM account using your email client i.e. Outlook and a copy of the email has landed inside a different contacts record, this could be explained due to the following reasons:
1. You have the contacts email address stored not just inside the contact record it should be associated with but also inside a contact record for another contact and your email has 'landed' inside that 'other' contacts record.
2. You have manually forwarded your email into the contacts specific CRM record - click here to see how to do this and you need to instead make sure you manually forward the email you sent/received into the correct contacts record.