Previously I was always able to filter on status code using -s. However if I do so now I get the following error:
Error: error on parsing arguments: status-codes and status-codes-blacklist are both set, pleaes set only one

Command I used:
gobuster dir -u http://127.0.0.1/ -w /usr/share/seclists/Discovery/Web-Content/big.txt -s "200"