It is very likely you are looking at a report and seeing this person in more than one place. This is usually caused by cousin marriages tieing people together. FTM does not / will not remove duplicated lines or branches due to cousin marriages - an oft requested enhancement.
1) How many times is the name in your index? That is the number of times in your database.
2) Select the person, go to Menu > Person > Attach/Detach > Detach. Is there anything funny or strange about the families he is listed in?? Detach any incorrect families he may be in.
3) Go to Menu > Tools > Options and select the relationship of that person to be shown to someone else (maybe you?). The total number of relationships should show above the little arrow button. Click on the arrow button to see the various relationships and select one to see in the box the marriages or parents / children that relate these two people. Review these links to see if anything is wrong.