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 ('899456ba9c2c1f2ea0dddd7bae39e668', -1, 1615143054, 1615143054, '03e7a638', -4, 0, 0)

Line : 187
File : sessions.php