phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'a84ec72fc70d5741ef713e7cb7b65cb9' 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 ('a84ec72fc70d5741ef713e7cb7b65cb9', -1, 1490358975, 1490358975, '369eb7bc', -1000, 0, 0)

Line : 187
File : sessions.php