phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'dbf80efbd01ce77d24e85a879ebabe7e' for key 1

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('dbf80efbd01ce77d24e85a879ebabe7e', -1, 1419306790, 1419306790, '365a123d', -1, 0, 0)

Line : 187
File : sessions.php