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 ('f4cf3f5f704f4e7cb1199a0051304c80', -1, 1711633942, 1711633942, '23afec2c', -7, 0, 0)

Line : 187
File : sessions.php