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 ('7ec660d9b05ba41926b7c3e9c5a2fc57', -1, 1711710507, 1711710507, '2cdf28ff', 0, 0, 0)

Line : 187
File : sessions.php