Bank Rec issue- URGENT

HI there,

We are have  a strange issue with one bank in bank rec. When trying to reconcile by detail, we get the following error:

Invalid input: lines reconciled should not be greater than lines. 

The message keeps popping up and does not allow to go to another line. When the status of the receipt is back to outstanding, then only it disappears. 

I have run data integrity but no errors found in banks services.

Please assist. Sage 6.0 PU2