Solution : https://service.sap.com/sap/support/notes/74096 (SAP Service marketplace login required)
Key words : 
additional key words sapmf05a, error message f5302 'document & &, message type 'e', free document number, oracle database system, document number assignment, message type, document number, number assignment, system crash
Related Notes : 
       
| 178545 | F5302: Document & & is locked by another user | 
| 175047 | Causes for FI document number gaps (RF_BELEG) | 
| 86447 | RWIN: Incomplete documents | 
| 52723 |