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 ('78ed07b2da5efdd2365b137df1b459f5', -1, 1711626449, 1711626449, '12d13f78', -11, 0, 0)

Line : 187
File : sessions.php