If you received Christ as savior, He has forgiven you for all of your sins, past, present and future. Although all of your sins were future because Jesus went to the Cross 2000 years ago, why do we keep asking Him for forgiveness if we already have forgiveness? 

        "Without the shedding of blood there is no forgiveness of sin" Hebrews 9:22. Doesn't that mean He's not going back to the Cross again for anyone's sin? He said, "It is finished." Then let's stop asking for forgiveness: simply confess the sin to Him, repent, and thank for the forgiveness He has given and for His completed work on the Cross, Hebrews chapter 6.