If no transactions appear in the Revalue Debtors or Creditors screen, this is usually because one of the following conditions applies.
The revalue process uses unallocated Foreign Currency transactions up to the current period for the Customer or Supplier and calculates a new Home Currency. Therefore, if there are no unallocated transactions in the range, none will appear. Additionally, if the unallocated transactions sum to zero, there will be nothing to revalue.