phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '0' 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 ('baa59d6a1b13727b8cde70f425c2a5a6', -1, 1539928629, 1539928629, '36e11a2c', -4, 0, 0)

Line : 187
File : sessions.php