phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 'session_user_id'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('a48742d4bb1e3b06141f706b807e77f1', -1, 1711644746, 1711644746, '2cc983d5', -1, 0, 0)

Line : 187
File : sessions.php