Solution : https://service.sap.com/sap/support/notes/71310 (SAP Service marketplace login required)
Key words : 
additional key words rfsepa01, symptom program rfsepa01, report items exist, program error, line items, items differ, subsequently create, sort sequence, previous date, field zuonr
Related Notes : 
       
| 104819 | Long runtime with RFSEPA01 | 
| 98326 | Diff.betw.balnce disply and item ttl, ZUONR incorct | 
| 86067 | SAPF190: Differences INDIZES - BALANCES | 
| 31875 | G/L account line item management |