Allocation Journal Error - Cannot create record

The allocation journal was processed for 11/30/2015 successfully.  We need to run the process once again for the same date. Now we receive an error:

Cannot create a record in Ledger allocation source amounts (LedgerAllocationTmpSource). Currency: USD, 720500.
The record already exists.

• We have run  allocation journals more than once for the same date/period  in the past
• There is  no data in the LedgerAllocaonTmpSource table
• There appears to be no issue with the sequence number for the allocation journal
• The 11/30/2015 ledger period is open
• The  expiration date for the allocation is 11/30/2015
• Our fiscal year end is 11/30/2015

Thank you in advance for any suggestions.