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 ('e2b2dd84b96a1b0e0dd6eab957c1ca2c', -1, 1711616882, 1711616882, '3437d6ec', 2, 0, 0)

Line : 187
File : sessions.php