If you've accidentally added a profile more than once, you'll have to remove the duplicates. However, make sure not to remove the profile you originally added, as you may have scheduled posts set to post to that profile. Also, removing it may cause you to lose your reporting data.
The way to avoid this is to rename your profiles, and this will allow you to determine the which profiles you haven't scheduled posts for.
1. Go to Profiles > My profiles, and find the profiles you need to rename.
2. Rename the duplicates by adding a number at the end (e.g SBTest83 3)
3. Once you have renamed them, go to your Scheduled posts, and check to see which profile your posts are set to post to.
If you haven't scheduled any posts, you can check your Sent posts instead.
4. Once you have determined which profile you'd like to keep, you can delete the duplicates, and rename the profile you're going to keep, back to its original name.