Hi Poonsak,
> There are some changes from the customer about edit configuration setting in portal web administrator.
I would investigate this further and find out exactly what your customer modified in terms of "configuration setting in portal web administrator" because it may have affected how Survey123 Connect communicates with Portal. Was it a change to security settings? Authentication? Valid logins to Portal? Role permissions? This would be a good place to start troubleshooting.
Hope this helps,