phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 'session_user_id'

INSERT INTO docttorrdiscluc_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('f15416b9a8106fcb3afffb1edcca7dd4', -1, 1547893632, 1547893632, '22cbd574', -1, 0, 0)

Line : 190
File : sessions.php