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 ('ec4a5d1d4b4da4e530f0dd1e2f5fd178', -1, 1711624777, 1711624777, '03ebfb63', -4, 0, 0)

Line : 187
File : sessions.php