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 ('16e7086bf97aede3d7e62a1e40210702', -1, 1711654904, 1711654904, '22e4a8c8', -4, 0, 0)

Line : 187
File : sessions.php