Solution : https://service.sap.com/sap/support/notes/1624763 (SAP Service marketplace login required)
Key words : 
approval screen solution apply, end user form reason, end user form, prerequisites email id, approval screen, user details, terms ac 10, access control 2010, correction instructions
Related Notes : 
       
| 1643205 | UAM: Email validation is not correct in access request | 
| 1607067 | Master Note for SAP Access Control 10.0 - Support Pack 6 |