phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '897ea8df041d43ed7762ed3f89600966' for key 'PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('897ea8df041d43ed7762ed3f89600966', -1, 1422676727, 1422676727, '369fe2cb', 15, 0, 0)

Line : 245
File : sessions.php