This error means, in your API response, the attribute that you mapped to account name is blank for a record. Saviynt can't import that record into accounts table.

"name": "userName~#~char",

Per your description, you have mentioned about 401 error during import. Could you share the log snippet to check?

Just add below in the configJson of your connector for detailed logs.

{"showLogs": true}

-Siva