You must have Admin Level - Webmaster access to delete individual results from meet results.
Click Events & Competition > Meet Results from the left navigation menu.
Click the Results By Meets tab.
Click the desired meet name.
Search for a swimmer.
Click the Delete link next to the record to remove it.
NOTE: If you do not see the Delete link by a result, it's because the LSC-Team code does not match yours, the athlete's ID does not match any in your database, or you do not have an admin level of at least a Webmaster. Please contact Support if you have questions.