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 ('762e189e2c01c28ec8366308b63bb42f', -1, 1781513398, 1781513398, 'd849d970', -9, 0, 0)

Line : 189
File : sessions.php