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 ('50c9959b79a4d1b416eab04933ad4386', -1, 1710832770, 1710832770, '36e2deb7', 6, 0, 0)

Line : 187
File : sessions.php