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 ('24566f5ac66bc43ecdd3f4b793e7051d', -1, 1534788650, 1534788650, '3651c423', 74, 0, 0)

Line : 187
File : sessions.php