ODBC Query in dataflows - keep getting asked to edit credentials when using a SQL statement

Hi,

Im trying to connect to amazon redshift via the ODBC connector in dataflows but am experiencing an issue where the service keeps asking me to edit credentials when I use a SQL statement. 

If I dont use a statement, I am able to navigate through the folders and access the smaller tables, however the table I am trying to get at has 50 million rows so I need a SQL statement to cut it down.

I have tried anonymous, organisational, basic and windows but none seem to be working. Frustratingly, I am certain it was working earlier this morning but now is not. 

Thanks