Customer opening balance?

[PaulaJ9874 at aol.com]

Hi, have just input a years worth of transactions into gnucash doing bank  
and account reconcilliations along the way.  Everything was fine until I  
ran customer reports.  All but one report showed only transactions for the  
period with balance credits and debits and an accurate account balance which  
coresponded with the aged-debt report.  One however showed balanced debits  
and credits but an amount owed which hadn't showed on the aged-debt  report. 
 after inspection I found the first entry on the report was not a  
transaction but a balance entry for the said amount.  How on earth this  balance got 
to be there I don't know and I cannot find a way to remove it.   If I issue 
a credit then the period totals will not balance.  I really  don't want to 
have to start over. 
 Paula.