phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'a0ef0bc66c2b3f0214f77c4ac78087ff' for key 'phpbb_sessions.PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('a0ef0bc66c2b3f0214f77c4ac78087ff', -1, 1770060469, 1770060469, 'd849d817', -4, 0, 0)

Line : 187
File : sessions.php